Migdal et al, Equation (51)

Percentage Accurate: 99.4% → 99.5%
Time: 12.8s
Alternatives: 11
Speedup: 1.0×

Specification

?
\[\begin{array}{l} \\ \frac{1}{\sqrt{k}} \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(\frac{1 - k}{2}\right)} \end{array} \]
(FPCore (k n)
 :precision binary64
 (* (/ 1.0 (sqrt k)) (pow (* (* 2.0 PI) n) (/ (- 1.0 k) 2.0))))
double code(double k, double n) {
	return (1.0 / sqrt(k)) * pow(((2.0 * ((double) M_PI)) * n), ((1.0 - k) / 2.0));
}
public static double code(double k, double n) {
	return (1.0 / Math.sqrt(k)) * Math.pow(((2.0 * Math.PI) * n), ((1.0 - k) / 2.0));
}
def code(k, n):
	return (1.0 / math.sqrt(k)) * math.pow(((2.0 * math.pi) * n), ((1.0 - k) / 2.0))
function code(k, n)
	return Float64(Float64(1.0 / sqrt(k)) * (Float64(Float64(2.0 * pi) * n) ^ Float64(Float64(1.0 - k) / 2.0)))
end
function tmp = code(k, n)
	tmp = (1.0 / sqrt(k)) * (((2.0 * pi) * n) ^ ((1.0 - k) / 2.0));
end
code[k_, n_] := N[(N[(1.0 / N[Sqrt[k], $MachinePrecision]), $MachinePrecision] * N[Power[N[(N[(2.0 * Pi), $MachinePrecision] * n), $MachinePrecision], N[(N[(1.0 - k), $MachinePrecision] / 2.0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{1}{\sqrt{k}} \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(\frac{1 - k}{2}\right)}
\end{array}

Sampling outcomes in binary64 precision:

Local Percentage Accuracy vs ?

The average percentage accuracy by input value. Horizontal axis shows value of an input variable; the variable is choosen in the title. Vertical axis is accuracy; higher is better. Red represent the original program, while blue represents Herbie's suggestion. These can be toggled with buttons below the plot. The line is an average while dots represent individual samples.

Accuracy vs Speed?

Herbie found 11 alternatives:

AlternativeAccuracySpeedup
The accuracy (vertical axis) and speed (horizontal axis) of each alternatives. Up and to the right is better. The red square shows the initial program, and each blue circle shows an alternative.The line shows the best available speed-accuracy tradeoffs.

Initial Program: 99.4% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \frac{1}{\sqrt{k}} \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(\frac{1 - k}{2}\right)} \end{array} \]
(FPCore (k n)
 :precision binary64
 (* (/ 1.0 (sqrt k)) (pow (* (* 2.0 PI) n) (/ (- 1.0 k) 2.0))))
double code(double k, double n) {
	return (1.0 / sqrt(k)) * pow(((2.0 * ((double) M_PI)) * n), ((1.0 - k) / 2.0));
}
public static double code(double k, double n) {
	return (1.0 / Math.sqrt(k)) * Math.pow(((2.0 * Math.PI) * n), ((1.0 - k) / 2.0));
}
def code(k, n):
	return (1.0 / math.sqrt(k)) * math.pow(((2.0 * math.pi) * n), ((1.0 - k) / 2.0))
function code(k, n)
	return Float64(Float64(1.0 / sqrt(k)) * (Float64(Float64(2.0 * pi) * n) ^ Float64(Float64(1.0 - k) / 2.0)))
end
function tmp = code(k, n)
	tmp = (1.0 / sqrt(k)) * (((2.0 * pi) * n) ^ ((1.0 - k) / 2.0));
end
code[k_, n_] := N[(N[(1.0 / N[Sqrt[k], $MachinePrecision]), $MachinePrecision] * N[Power[N[(N[(2.0 * Pi), $MachinePrecision] * n), $MachinePrecision], N[(N[(1.0 - k), $MachinePrecision] / 2.0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{1}{\sqrt{k}} \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(\frac{1 - k}{2}\right)}
\end{array}

Alternative 1: 99.5% accurate, 0.6× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := \pi \cdot \left(2 \cdot n\right)\\ \frac{\frac{\sqrt{t_0}}{{t_0}^{\left(k \cdot 0.5\right)}}}{\sqrt{k}} \end{array} \end{array} \]
(FPCore (k n)
 :precision binary64
 (let* ((t_0 (* PI (* 2.0 n))))
   (/ (/ (sqrt t_0) (pow t_0 (* k 0.5))) (sqrt k))))
double code(double k, double n) {
	double t_0 = ((double) M_PI) * (2.0 * n);
	return (sqrt(t_0) / pow(t_0, (k * 0.5))) / sqrt(k);
}
public static double code(double k, double n) {
	double t_0 = Math.PI * (2.0 * n);
	return (Math.sqrt(t_0) / Math.pow(t_0, (k * 0.5))) / Math.sqrt(k);
}
def code(k, n):
	t_0 = math.pi * (2.0 * n)
	return (math.sqrt(t_0) / math.pow(t_0, (k * 0.5))) / math.sqrt(k)
function code(k, n)
	t_0 = Float64(pi * Float64(2.0 * n))
	return Float64(Float64(sqrt(t_0) / (t_0 ^ Float64(k * 0.5))) / sqrt(k))
end
function tmp = code(k, n)
	t_0 = pi * (2.0 * n);
	tmp = (sqrt(t_0) / (t_0 ^ (k * 0.5))) / sqrt(k);
end
code[k_, n_] := Block[{t$95$0 = N[(Pi * N[(2.0 * n), $MachinePrecision]), $MachinePrecision]}, N[(N[(N[Sqrt[t$95$0], $MachinePrecision] / N[Power[t$95$0, N[(k * 0.5), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] / N[Sqrt[k], $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := \pi \cdot \left(2 \cdot n\right)\\
\frac{\frac{\sqrt{t_0}}{{t_0}^{\left(k \cdot 0.5\right)}}}{\sqrt{k}}
\end{array}
\end{array}
Derivation
  1. Initial program 99.5%

    \[\frac{1}{\sqrt{k}} \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(\frac{1 - k}{2}\right)} \]
  2. Step-by-step derivation
    1. div-sub99.5%

      \[\leadsto \frac{1}{\sqrt{k}} \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\color{blue}{\left(\frac{1}{2} - \frac{k}{2}\right)}} \]
    2. metadata-eval99.5%

      \[\leadsto \frac{1}{\sqrt{k}} \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(\color{blue}{0.5} - \frac{k}{2}\right)} \]
    3. pow-sub99.6%

      \[\leadsto \frac{1}{\sqrt{k}} \cdot \color{blue}{\frac{{\left(\left(2 \cdot \pi\right) \cdot n\right)}^{0.5}}{{\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(\frac{k}{2}\right)}}} \]
    4. pow1/299.6%

      \[\leadsto \frac{1}{\sqrt{k}} \cdot \frac{\color{blue}{\sqrt{\left(2 \cdot \pi\right) \cdot n}}}{{\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(\frac{k}{2}\right)}} \]
    5. associate-*l*99.6%

      \[\leadsto \frac{1}{\sqrt{k}} \cdot \frac{\sqrt{\color{blue}{2 \cdot \left(\pi \cdot n\right)}}}{{\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(\frac{k}{2}\right)}} \]
    6. associate-*l*99.6%

      \[\leadsto \frac{1}{\sqrt{k}} \cdot \frac{\sqrt{2 \cdot \left(\pi \cdot n\right)}}{{\color{blue}{\left(2 \cdot \left(\pi \cdot n\right)\right)}}^{\left(\frac{k}{2}\right)}} \]
    7. div-inv99.6%

      \[\leadsto \frac{1}{\sqrt{k}} \cdot \frac{\sqrt{2 \cdot \left(\pi \cdot n\right)}}{{\left(2 \cdot \left(\pi \cdot n\right)\right)}^{\color{blue}{\left(k \cdot \frac{1}{2}\right)}}} \]
    8. metadata-eval99.6%

      \[\leadsto \frac{1}{\sqrt{k}} \cdot \frac{\sqrt{2 \cdot \left(\pi \cdot n\right)}}{{\left(2 \cdot \left(\pi \cdot n\right)\right)}^{\left(k \cdot \color{blue}{0.5}\right)}} \]
  3. Applied egg-rr99.6%

    \[\leadsto \frac{1}{\sqrt{k}} \cdot \color{blue}{\frac{\sqrt{2 \cdot \left(\pi \cdot n\right)}}{{\left(2 \cdot \left(\pi \cdot n\right)\right)}^{\left(k \cdot 0.5\right)}}} \]
  4. Step-by-step derivation
    1. *-commutative99.6%

      \[\leadsto \frac{1}{\sqrt{k}} \cdot \frac{\sqrt{2 \cdot \color{blue}{\left(n \cdot \pi\right)}}}{{\left(2 \cdot \left(\pi \cdot n\right)\right)}^{\left(k \cdot 0.5\right)}} \]
    2. associate-*r*99.6%

      \[\leadsto \frac{1}{\sqrt{k}} \cdot \frac{\sqrt{\color{blue}{\left(2 \cdot n\right) \cdot \pi}}}{{\left(2 \cdot \left(\pi \cdot n\right)\right)}^{\left(k \cdot 0.5\right)}} \]
    3. *-commutative99.6%

      \[\leadsto \frac{1}{\sqrt{k}} \cdot \frac{\sqrt{\left(2 \cdot n\right) \cdot \pi}}{{\left(2 \cdot \color{blue}{\left(n \cdot \pi\right)}\right)}^{\left(k \cdot 0.5\right)}} \]
    4. associate-*r*99.6%

      \[\leadsto \frac{1}{\sqrt{k}} \cdot \frac{\sqrt{\left(2 \cdot n\right) \cdot \pi}}{{\color{blue}{\left(\left(2 \cdot n\right) \cdot \pi\right)}}^{\left(k \cdot 0.5\right)}} \]
  5. Simplified99.6%

    \[\leadsto \frac{1}{\sqrt{k}} \cdot \color{blue}{\frac{\sqrt{\left(2 \cdot n\right) \cdot \pi}}{{\left(\left(2 \cdot n\right) \cdot \pi\right)}^{\left(k \cdot 0.5\right)}}} \]
  6. Step-by-step derivation
    1. associate-*l/99.7%

      \[\leadsto \color{blue}{\frac{1 \cdot \frac{\sqrt{\left(2 \cdot n\right) \cdot \pi}}{{\left(\left(2 \cdot n\right) \cdot \pi\right)}^{\left(k \cdot 0.5\right)}}}{\sqrt{k}}} \]
    2. *-un-lft-identity99.7%

      \[\leadsto \frac{\color{blue}{\frac{\sqrt{\left(2 \cdot n\right) \cdot \pi}}{{\left(\left(2 \cdot n\right) \cdot \pi\right)}^{\left(k \cdot 0.5\right)}}}}{\sqrt{k}} \]
    3. *-commutative99.7%

      \[\leadsto \frac{\frac{\sqrt{\color{blue}{\pi \cdot \left(2 \cdot n\right)}}}{{\left(\left(2 \cdot n\right) \cdot \pi\right)}^{\left(k \cdot 0.5\right)}}}{\sqrt{k}} \]
    4. *-commutative99.7%

      \[\leadsto \frac{\frac{\sqrt{\pi \cdot \left(2 \cdot n\right)}}{{\color{blue}{\left(\pi \cdot \left(2 \cdot n\right)\right)}}^{\left(k \cdot 0.5\right)}}}{\sqrt{k}} \]
  7. Applied egg-rr99.7%

    \[\leadsto \color{blue}{\frac{\frac{\sqrt{\pi \cdot \left(2 \cdot n\right)}}{{\left(\pi \cdot \left(2 \cdot n\right)\right)}^{\left(k \cdot 0.5\right)}}}{\sqrt{k}}} \]
  8. Final simplification99.7%

    \[\leadsto \frac{\frac{\sqrt{\pi \cdot \left(2 \cdot n\right)}}{{\left(\pi \cdot \left(2 \cdot n\right)\right)}^{\left(k \cdot 0.5\right)}}}{\sqrt{k}} \]

Alternative 2: 99.4% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;k \leq 2.7 \cdot 10^{-20}:\\ \;\;\;\;\sqrt{n + n} \cdot \sqrt{\frac{\pi}{k}}\\ \mathbf{else}:\\ \;\;\;\;\frac{1}{\sqrt{\frac{k}{{\left(2 \cdot \left(\pi \cdot n\right)\right)}^{\left(1 - k\right)}}}}\\ \end{array} \end{array} \]
(FPCore (k n)
 :precision binary64
 (if (<= k 2.7e-20)
   (* (sqrt (+ n n)) (sqrt (/ PI k)))
   (/ 1.0 (sqrt (/ k (pow (* 2.0 (* PI n)) (- 1.0 k)))))))
double code(double k, double n) {
	double tmp;
	if (k <= 2.7e-20) {
		tmp = sqrt((n + n)) * sqrt((((double) M_PI) / k));
	} else {
		tmp = 1.0 / sqrt((k / pow((2.0 * (((double) M_PI) * n)), (1.0 - k))));
	}
	return tmp;
}
public static double code(double k, double n) {
	double tmp;
	if (k <= 2.7e-20) {
		tmp = Math.sqrt((n + n)) * Math.sqrt((Math.PI / k));
	} else {
		tmp = 1.0 / Math.sqrt((k / Math.pow((2.0 * (Math.PI * n)), (1.0 - k))));
	}
	return tmp;
}
def code(k, n):
	tmp = 0
	if k <= 2.7e-20:
		tmp = math.sqrt((n + n)) * math.sqrt((math.pi / k))
	else:
		tmp = 1.0 / math.sqrt((k / math.pow((2.0 * (math.pi * n)), (1.0 - k))))
	return tmp
function code(k, n)
	tmp = 0.0
	if (k <= 2.7e-20)
		tmp = Float64(sqrt(Float64(n + n)) * sqrt(Float64(pi / k)));
	else
		tmp = Float64(1.0 / sqrt(Float64(k / (Float64(2.0 * Float64(pi * n)) ^ Float64(1.0 - k)))));
	end
	return tmp
end
function tmp_2 = code(k, n)
	tmp = 0.0;
	if (k <= 2.7e-20)
		tmp = sqrt((n + n)) * sqrt((pi / k));
	else
		tmp = 1.0 / sqrt((k / ((2.0 * (pi * n)) ^ (1.0 - k))));
	end
	tmp_2 = tmp;
end
code[k_, n_] := If[LessEqual[k, 2.7e-20], N[(N[Sqrt[N[(n + n), $MachinePrecision]], $MachinePrecision] * N[Sqrt[N[(Pi / k), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], N[(1.0 / N[Sqrt[N[(k / N[Power[N[(2.0 * N[(Pi * n), $MachinePrecision]), $MachinePrecision], N[(1.0 - k), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;k \leq 2.7 \cdot 10^{-20}:\\
\;\;\;\;\sqrt{n + n} \cdot \sqrt{\frac{\pi}{k}}\\

\mathbf{else}:\\
\;\;\;\;\frac{1}{\sqrt{\frac{k}{{\left(2 \cdot \left(\pi \cdot n\right)\right)}^{\left(1 - k\right)}}}}\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if k < 2.7e-20

    1. Initial program 99.2%

      \[\frac{1}{\sqrt{k}} \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(\frac{1 - k}{2}\right)} \]
    2. Step-by-step derivation
      1. *-commutative99.2%

        \[\leadsto \color{blue}{{\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(\frac{1 - k}{2}\right)} \cdot \frac{1}{\sqrt{k}}} \]
      2. *-commutative99.2%

        \[\leadsto {\left(\color{blue}{\left(\pi \cdot 2\right)} \cdot n\right)}^{\left(\frac{1 - k}{2}\right)} \cdot \frac{1}{\sqrt{k}} \]
      3. associate-*r*99.2%

        \[\leadsto {\color{blue}{\left(\pi \cdot \left(2 \cdot n\right)\right)}}^{\left(\frac{1 - k}{2}\right)} \cdot \frac{1}{\sqrt{k}} \]
      4. div-inv99.3%

        \[\leadsto \color{blue}{\frac{{\left(\pi \cdot \left(2 \cdot n\right)\right)}^{\left(\frac{1 - k}{2}\right)}}{\sqrt{k}}} \]
      5. expm1-log1p-u93.8%

        \[\leadsto \color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\frac{{\left(\pi \cdot \left(2 \cdot n\right)\right)}^{\left(\frac{1 - k}{2}\right)}}{\sqrt{k}}\right)\right)} \]
      6. expm1-udef67.5%

        \[\leadsto \color{blue}{e^{\mathsf{log1p}\left(\frac{{\left(\pi \cdot \left(2 \cdot n\right)\right)}^{\left(\frac{1 - k}{2}\right)}}{\sqrt{k}}\right)} - 1} \]
    3. Applied egg-rr40.9%

      \[\leadsto \color{blue}{e^{\mathsf{log1p}\left(\sqrt{\frac{{\left(2 \cdot \left(\pi \cdot n\right)\right)}^{\left(1 - k\right)}}{k}}\right)} - 1} \]
    4. Step-by-step derivation
      1. expm1-def67.3%

        \[\leadsto \color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\sqrt{\frac{{\left(2 \cdot \left(\pi \cdot n\right)\right)}^{\left(1 - k\right)}}{k}}\right)\right)} \]
      2. expm1-log1p70.0%

        \[\leadsto \color{blue}{\sqrt{\frac{{\left(2 \cdot \left(\pi \cdot n\right)\right)}^{\left(1 - k\right)}}{k}}} \]
      3. *-commutative70.0%

        \[\leadsto \sqrt{\frac{{\left(2 \cdot \color{blue}{\left(n \cdot \pi\right)}\right)}^{\left(1 - k\right)}}{k}} \]
      4. associate-*r*70.0%

        \[\leadsto \sqrt{\frac{{\color{blue}{\left(\left(2 \cdot n\right) \cdot \pi\right)}}^{\left(1 - k\right)}}{k}} \]
    5. Simplified70.0%

      \[\leadsto \color{blue}{\sqrt{\frac{{\left(\left(2 \cdot n\right) \cdot \pi\right)}^{\left(1 - k\right)}}{k}}} \]
    6. Taylor expanded in k around 0 70.0%

      \[\leadsto \sqrt{\color{blue}{2 \cdot \frac{n \cdot \pi}{k}}} \]
    7. Step-by-step derivation
      1. associate-/l*70.0%

        \[\leadsto \sqrt{2 \cdot \color{blue}{\frac{n}{\frac{k}{\pi}}}} \]
    8. Simplified70.0%

      \[\leadsto \sqrt{\color{blue}{2 \cdot \frac{n}{\frac{k}{\pi}}}} \]
    9. Taylor expanded in n around 0 70.0%

      \[\leadsto \sqrt{2 \cdot \color{blue}{\frac{n \cdot \pi}{k}}} \]
    10. Step-by-step derivation
      1. associate-/l*70.0%

        \[\leadsto \sqrt{2 \cdot \color{blue}{\frac{n}{\frac{k}{\pi}}}} \]
      2. *-rgt-identity70.0%

        \[\leadsto \sqrt{2 \cdot \frac{\color{blue}{n \cdot 1}}{\frac{k}{\pi}}} \]
      3. associate-*r/69.9%

        \[\leadsto \sqrt{2 \cdot \color{blue}{\left(n \cdot \frac{1}{\frac{k}{\pi}}\right)}} \]
      4. associate-/r/70.0%

        \[\leadsto \sqrt{2 \cdot \left(n \cdot \color{blue}{\left(\frac{1}{k} \cdot \pi\right)}\right)} \]
      5. associate-*l/70.0%

        \[\leadsto \sqrt{2 \cdot \left(n \cdot \color{blue}{\frac{1 \cdot \pi}{k}}\right)} \]
      6. *-lft-identity70.0%

        \[\leadsto \sqrt{2 \cdot \left(n \cdot \frac{\color{blue}{\pi}}{k}\right)} \]
    11. Simplified70.0%

      \[\leadsto \sqrt{2 \cdot \color{blue}{\left(n \cdot \frac{\pi}{k}\right)}} \]
    12. Step-by-step derivation
      1. pow1/270.0%

        \[\leadsto \color{blue}{{\left(2 \cdot \left(n \cdot \frac{\pi}{k}\right)\right)}^{0.5}} \]
      2. associate-*r*70.0%

        \[\leadsto {\color{blue}{\left(\left(2 \cdot n\right) \cdot \frac{\pi}{k}\right)}}^{0.5} \]
      3. *-commutative70.0%

        \[\leadsto {\left(\color{blue}{\left(n \cdot 2\right)} \cdot \frac{\pi}{k}\right)}^{0.5} \]
      4. unpow-prod-down99.3%

        \[\leadsto \color{blue}{{\left(n \cdot 2\right)}^{0.5} \cdot {\left(\frac{\pi}{k}\right)}^{0.5}} \]
      5. pow1/299.3%

        \[\leadsto \color{blue}{\sqrt{n \cdot 2}} \cdot {\left(\frac{\pi}{k}\right)}^{0.5} \]
      6. *-commutative99.3%

        \[\leadsto \sqrt{\color{blue}{2 \cdot n}} \cdot {\left(\frac{\pi}{k}\right)}^{0.5} \]
      7. pow1/299.3%

        \[\leadsto \sqrt{2 \cdot n} \cdot \color{blue}{\sqrt{\frac{\pi}{k}}} \]
    13. Applied egg-rr99.3%

      \[\leadsto \color{blue}{\sqrt{2 \cdot n} \cdot \sqrt{\frac{\pi}{k}}} \]
    14. Step-by-step derivation
      1. rem-log-exp7.0%

        \[\leadsto \sqrt{2 \cdot \color{blue}{\log \left(e^{n}\right)}} \cdot \sqrt{\frac{\pi}{k}} \]
      2. log-pow7.1%

        \[\leadsto \sqrt{\color{blue}{\log \left({\left(e^{n}\right)}^{2}\right)}} \cdot \sqrt{\frac{\pi}{k}} \]
      3. unpow27.1%

        \[\leadsto \sqrt{\log \color{blue}{\left(e^{n} \cdot e^{n}\right)}} \cdot \sqrt{\frac{\pi}{k}} \]
      4. log-prod7.0%

        \[\leadsto \sqrt{\color{blue}{\log \left(e^{n}\right) + \log \left(e^{n}\right)}} \cdot \sqrt{\frac{\pi}{k}} \]
      5. rem-log-exp15.0%

        \[\leadsto \sqrt{\color{blue}{n} + \log \left(e^{n}\right)} \cdot \sqrt{\frac{\pi}{k}} \]
      6. rem-log-exp99.3%

        \[\leadsto \sqrt{n + \color{blue}{n}} \cdot \sqrt{\frac{\pi}{k}} \]
    15. Simplified99.3%

      \[\leadsto \color{blue}{\sqrt{n + n} \cdot \sqrt{\frac{\pi}{k}}} \]

    if 2.7e-20 < k

    1. Initial program 99.8%

      \[\frac{1}{\sqrt{k}} \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(\frac{1 - k}{2}\right)} \]
    2. Step-by-step derivation
      1. add-sqr-sqrt99.8%

        \[\leadsto \color{blue}{\left(\sqrt{\frac{1}{\sqrt{k}}} \cdot \sqrt{\frac{1}{\sqrt{k}}}\right)} \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(\frac{1 - k}{2}\right)} \]
      2. sqrt-unprod99.8%

        \[\leadsto \color{blue}{\sqrt{\frac{1}{\sqrt{k}} \cdot \frac{1}{\sqrt{k}}}} \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(\frac{1 - k}{2}\right)} \]
      3. frac-times99.8%

        \[\leadsto \sqrt{\color{blue}{\frac{1 \cdot 1}{\sqrt{k} \cdot \sqrt{k}}}} \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(\frac{1 - k}{2}\right)} \]
      4. metadata-eval99.8%

        \[\leadsto \sqrt{\frac{\color{blue}{1}}{\sqrt{k} \cdot \sqrt{k}}} \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(\frac{1 - k}{2}\right)} \]
      5. add-sqr-sqrt99.8%

        \[\leadsto \sqrt{\frac{1}{\color{blue}{k}}} \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(\frac{1 - k}{2}\right)} \]
    3. Applied egg-rr99.8%

      \[\leadsto \color{blue}{\sqrt{\frac{1}{k}}} \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(\frac{1 - k}{2}\right)} \]
    4. Step-by-step derivation
      1. *-commutative99.8%

        \[\leadsto \color{blue}{{\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(\frac{1 - k}{2}\right)} \cdot \sqrt{\frac{1}{k}}} \]
      2. associate-*r*99.8%

        \[\leadsto {\color{blue}{\left(2 \cdot \left(\pi \cdot n\right)\right)}}^{\left(\frac{1 - k}{2}\right)} \cdot \sqrt{\frac{1}{k}} \]
      3. sqrt-pow199.8%

        \[\leadsto \color{blue}{\sqrt{{\left(2 \cdot \left(\pi \cdot n\right)\right)}^{\left(1 - k\right)}}} \cdot \sqrt{\frac{1}{k}} \]
      4. sqrt-prod99.8%

        \[\leadsto \color{blue}{\sqrt{{\left(2 \cdot \left(\pi \cdot n\right)\right)}^{\left(1 - k\right)} \cdot \frac{1}{k}}} \]
      5. div-inv99.8%

        \[\leadsto \sqrt{\color{blue}{\frac{{\left(2 \cdot \left(\pi \cdot n\right)\right)}^{\left(1 - k\right)}}{k}}} \]
      6. clear-num99.8%

        \[\leadsto \sqrt{\color{blue}{\frac{1}{\frac{k}{{\left(2 \cdot \left(\pi \cdot n\right)\right)}^{\left(1 - k\right)}}}}} \]
      7. sqrt-div99.8%

        \[\leadsto \color{blue}{\frac{\sqrt{1}}{\sqrt{\frac{k}{{\left(2 \cdot \left(\pi \cdot n\right)\right)}^{\left(1 - k\right)}}}}} \]
      8. metadata-eval99.8%

        \[\leadsto \frac{\color{blue}{1}}{\sqrt{\frac{k}{{\left(2 \cdot \left(\pi \cdot n\right)\right)}^{\left(1 - k\right)}}}} \]
    5. Applied egg-rr99.8%

      \[\leadsto \color{blue}{\frac{1}{\sqrt{\frac{k}{{\left(2 \cdot \left(\pi \cdot n\right)\right)}^{\left(1 - k\right)}}}}} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification99.6%

    \[\leadsto \begin{array}{l} \mathbf{if}\;k \leq 2.7 \cdot 10^{-20}:\\ \;\;\;\;\sqrt{n + n} \cdot \sqrt{\frac{\pi}{k}}\\ \mathbf{else}:\\ \;\;\;\;\frac{1}{\sqrt{\frac{k}{{\left(2 \cdot \left(\pi \cdot n\right)\right)}^{\left(1 - k\right)}}}}\\ \end{array} \]

Alternative 3: 99.4% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \sqrt{\frac{1}{k}} \cdot {\left(n \cdot \left(\pi \cdot 2\right)\right)}^{\left(\frac{1 - k}{2}\right)} \end{array} \]
(FPCore (k n)
 :precision binary64
 (* (sqrt (/ 1.0 k)) (pow (* n (* PI 2.0)) (/ (- 1.0 k) 2.0))))
double code(double k, double n) {
	return sqrt((1.0 / k)) * pow((n * (((double) M_PI) * 2.0)), ((1.0 - k) / 2.0));
}
public static double code(double k, double n) {
	return Math.sqrt((1.0 / k)) * Math.pow((n * (Math.PI * 2.0)), ((1.0 - k) / 2.0));
}
def code(k, n):
	return math.sqrt((1.0 / k)) * math.pow((n * (math.pi * 2.0)), ((1.0 - k) / 2.0))
function code(k, n)
	return Float64(sqrt(Float64(1.0 / k)) * (Float64(n * Float64(pi * 2.0)) ^ Float64(Float64(1.0 - k) / 2.0)))
end
function tmp = code(k, n)
	tmp = sqrt((1.0 / k)) * ((n * (pi * 2.0)) ^ ((1.0 - k) / 2.0));
end
code[k_, n_] := N[(N[Sqrt[N[(1.0 / k), $MachinePrecision]], $MachinePrecision] * N[Power[N[(n * N[(Pi * 2.0), $MachinePrecision]), $MachinePrecision], N[(N[(1.0 - k), $MachinePrecision] / 2.0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\sqrt{\frac{1}{k}} \cdot {\left(n \cdot \left(\pi \cdot 2\right)\right)}^{\left(\frac{1 - k}{2}\right)}
\end{array}
Derivation
  1. Initial program 99.5%

    \[\frac{1}{\sqrt{k}} \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(\frac{1 - k}{2}\right)} \]
  2. Step-by-step derivation
    1. add-sqr-sqrt99.4%

      \[\leadsto \color{blue}{\left(\sqrt{\frac{1}{\sqrt{k}}} \cdot \sqrt{\frac{1}{\sqrt{k}}}\right)} \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(\frac{1 - k}{2}\right)} \]
    2. sqrt-unprod99.5%

      \[\leadsto \color{blue}{\sqrt{\frac{1}{\sqrt{k}} \cdot \frac{1}{\sqrt{k}}}} \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(\frac{1 - k}{2}\right)} \]
    3. frac-times99.6%

      \[\leadsto \sqrt{\color{blue}{\frac{1 \cdot 1}{\sqrt{k} \cdot \sqrt{k}}}} \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(\frac{1 - k}{2}\right)} \]
    4. metadata-eval99.6%

      \[\leadsto \sqrt{\frac{\color{blue}{1}}{\sqrt{k} \cdot \sqrt{k}}} \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(\frac{1 - k}{2}\right)} \]
    5. add-sqr-sqrt99.6%

      \[\leadsto \sqrt{\frac{1}{\color{blue}{k}}} \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(\frac{1 - k}{2}\right)} \]
  3. Applied egg-rr99.6%

    \[\leadsto \color{blue}{\sqrt{\frac{1}{k}}} \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(\frac{1 - k}{2}\right)} \]
  4. Final simplification99.6%

    \[\leadsto \sqrt{\frac{1}{k}} \cdot {\left(n \cdot \left(\pi \cdot 2\right)\right)}^{\left(\frac{1 - k}{2}\right)} \]

Alternative 4: 99.5% accurate, 1.0× speedup?

\[\begin{array}{l} \\ {\left(n \cdot \left(\pi \cdot 2\right)\right)}^{\left(\frac{1 - k}{2}\right)} \cdot {k}^{-0.5} \end{array} \]
(FPCore (k n)
 :precision binary64
 (* (pow (* n (* PI 2.0)) (/ (- 1.0 k) 2.0)) (pow k -0.5)))
double code(double k, double n) {
	return pow((n * (((double) M_PI) * 2.0)), ((1.0 - k) / 2.0)) * pow(k, -0.5);
}
public static double code(double k, double n) {
	return Math.pow((n * (Math.PI * 2.0)), ((1.0 - k) / 2.0)) * Math.pow(k, -0.5);
}
def code(k, n):
	return math.pow((n * (math.pi * 2.0)), ((1.0 - k) / 2.0)) * math.pow(k, -0.5)
function code(k, n)
	return Float64((Float64(n * Float64(pi * 2.0)) ^ Float64(Float64(1.0 - k) / 2.0)) * (k ^ -0.5))
end
function tmp = code(k, n)
	tmp = ((n * (pi * 2.0)) ^ ((1.0 - k) / 2.0)) * (k ^ -0.5);
end
code[k_, n_] := N[(N[Power[N[(n * N[(Pi * 2.0), $MachinePrecision]), $MachinePrecision], N[(N[(1.0 - k), $MachinePrecision] / 2.0), $MachinePrecision]], $MachinePrecision] * N[Power[k, -0.5], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
{\left(n \cdot \left(\pi \cdot 2\right)\right)}^{\left(\frac{1 - k}{2}\right)} \cdot {k}^{-0.5}
\end{array}
Derivation
  1. Initial program 99.5%

    \[\frac{1}{\sqrt{k}} \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(\frac{1 - k}{2}\right)} \]
  2. Step-by-step derivation
    1. expm1-log1p-u96.4%

      \[\leadsto \color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\frac{1}{\sqrt{k}}\right)\right)} \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(\frac{1 - k}{2}\right)} \]
    2. expm1-udef76.5%

      \[\leadsto \color{blue}{\left(e^{\mathsf{log1p}\left(\frac{1}{\sqrt{k}}\right)} - 1\right)} \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(\frac{1 - k}{2}\right)} \]
    3. pow1/276.5%

      \[\leadsto \left(e^{\mathsf{log1p}\left(\frac{1}{\color{blue}{{k}^{0.5}}}\right)} - 1\right) \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(\frac{1 - k}{2}\right)} \]
    4. pow-flip76.5%

      \[\leadsto \left(e^{\mathsf{log1p}\left(\color{blue}{{k}^{\left(-0.5\right)}}\right)} - 1\right) \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(\frac{1 - k}{2}\right)} \]
    5. metadata-eval76.5%

      \[\leadsto \left(e^{\mathsf{log1p}\left({k}^{\color{blue}{-0.5}}\right)} - 1\right) \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(\frac{1 - k}{2}\right)} \]
  3. Applied egg-rr76.5%

    \[\leadsto \color{blue}{\left(e^{\mathsf{log1p}\left({k}^{-0.5}\right)} - 1\right)} \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(\frac{1 - k}{2}\right)} \]
  4. Step-by-step derivation
    1. expm1-def96.4%

      \[\leadsto \color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left({k}^{-0.5}\right)\right)} \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(\frac{1 - k}{2}\right)} \]
    2. expm1-log1p99.6%

      \[\leadsto \color{blue}{{k}^{-0.5}} \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(\frac{1 - k}{2}\right)} \]
  5. Simplified99.6%

    \[\leadsto \color{blue}{{k}^{-0.5}} \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(\frac{1 - k}{2}\right)} \]
  6. Final simplification99.6%

    \[\leadsto {\left(n \cdot \left(\pi \cdot 2\right)\right)}^{\left(\frac{1 - k}{2}\right)} \cdot {k}^{-0.5} \]

Alternative 5: 99.3% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;k \leq 10^{-21}:\\ \;\;\;\;\sqrt{n + n} \cdot \sqrt{\frac{\pi}{k}}\\ \mathbf{else}:\\ \;\;\;\;\sqrt{\frac{{\left(\pi \cdot \left(2 \cdot n\right)\right)}^{\left(1 - k\right)}}{k}}\\ \end{array} \end{array} \]
(FPCore (k n)
 :precision binary64
 (if (<= k 1e-21)
   (* (sqrt (+ n n)) (sqrt (/ PI k)))
   (sqrt (/ (pow (* PI (* 2.0 n)) (- 1.0 k)) k))))
double code(double k, double n) {
	double tmp;
	if (k <= 1e-21) {
		tmp = sqrt((n + n)) * sqrt((((double) M_PI) / k));
	} else {
		tmp = sqrt((pow((((double) M_PI) * (2.0 * n)), (1.0 - k)) / k));
	}
	return tmp;
}
public static double code(double k, double n) {
	double tmp;
	if (k <= 1e-21) {
		tmp = Math.sqrt((n + n)) * Math.sqrt((Math.PI / k));
	} else {
		tmp = Math.sqrt((Math.pow((Math.PI * (2.0 * n)), (1.0 - k)) / k));
	}
	return tmp;
}
def code(k, n):
	tmp = 0
	if k <= 1e-21:
		tmp = math.sqrt((n + n)) * math.sqrt((math.pi / k))
	else:
		tmp = math.sqrt((math.pow((math.pi * (2.0 * n)), (1.0 - k)) / k))
	return tmp
function code(k, n)
	tmp = 0.0
	if (k <= 1e-21)
		tmp = Float64(sqrt(Float64(n + n)) * sqrt(Float64(pi / k)));
	else
		tmp = sqrt(Float64((Float64(pi * Float64(2.0 * n)) ^ Float64(1.0 - k)) / k));
	end
	return tmp
end
function tmp_2 = code(k, n)
	tmp = 0.0;
	if (k <= 1e-21)
		tmp = sqrt((n + n)) * sqrt((pi / k));
	else
		tmp = sqrt((((pi * (2.0 * n)) ^ (1.0 - k)) / k));
	end
	tmp_2 = tmp;
end
code[k_, n_] := If[LessEqual[k, 1e-21], N[(N[Sqrt[N[(n + n), $MachinePrecision]], $MachinePrecision] * N[Sqrt[N[(Pi / k), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], N[Sqrt[N[(N[Power[N[(Pi * N[(2.0 * n), $MachinePrecision]), $MachinePrecision], N[(1.0 - k), $MachinePrecision]], $MachinePrecision] / k), $MachinePrecision]], $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;k \leq 10^{-21}:\\
\;\;\;\;\sqrt{n + n} \cdot \sqrt{\frac{\pi}{k}}\\

\mathbf{else}:\\
\;\;\;\;\sqrt{\frac{{\left(\pi \cdot \left(2 \cdot n\right)\right)}^{\left(1 - k\right)}}{k}}\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if k < 9.99999999999999908e-22

    1. Initial program 99.2%

      \[\frac{1}{\sqrt{k}} \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(\frac{1 - k}{2}\right)} \]
    2. Step-by-step derivation
      1. *-commutative99.2%

        \[\leadsto \color{blue}{{\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(\frac{1 - k}{2}\right)} \cdot \frac{1}{\sqrt{k}}} \]
      2. *-commutative99.2%

        \[\leadsto {\left(\color{blue}{\left(\pi \cdot 2\right)} \cdot n\right)}^{\left(\frac{1 - k}{2}\right)} \cdot \frac{1}{\sqrt{k}} \]
      3. associate-*r*99.2%

        \[\leadsto {\color{blue}{\left(\pi \cdot \left(2 \cdot n\right)\right)}}^{\left(\frac{1 - k}{2}\right)} \cdot \frac{1}{\sqrt{k}} \]
      4. div-inv99.3%

        \[\leadsto \color{blue}{\frac{{\left(\pi \cdot \left(2 \cdot n\right)\right)}^{\left(\frac{1 - k}{2}\right)}}{\sqrt{k}}} \]
      5. expm1-log1p-u93.8%

        \[\leadsto \color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\frac{{\left(\pi \cdot \left(2 \cdot n\right)\right)}^{\left(\frac{1 - k}{2}\right)}}{\sqrt{k}}\right)\right)} \]
      6. expm1-udef67.5%

        \[\leadsto \color{blue}{e^{\mathsf{log1p}\left(\frac{{\left(\pi \cdot \left(2 \cdot n\right)\right)}^{\left(\frac{1 - k}{2}\right)}}{\sqrt{k}}\right)} - 1} \]
    3. Applied egg-rr40.9%

      \[\leadsto \color{blue}{e^{\mathsf{log1p}\left(\sqrt{\frac{{\left(2 \cdot \left(\pi \cdot n\right)\right)}^{\left(1 - k\right)}}{k}}\right)} - 1} \]
    4. Step-by-step derivation
      1. expm1-def67.3%

        \[\leadsto \color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\sqrt{\frac{{\left(2 \cdot \left(\pi \cdot n\right)\right)}^{\left(1 - k\right)}}{k}}\right)\right)} \]
      2. expm1-log1p70.0%

        \[\leadsto \color{blue}{\sqrt{\frac{{\left(2 \cdot \left(\pi \cdot n\right)\right)}^{\left(1 - k\right)}}{k}}} \]
      3. *-commutative70.0%

        \[\leadsto \sqrt{\frac{{\left(2 \cdot \color{blue}{\left(n \cdot \pi\right)}\right)}^{\left(1 - k\right)}}{k}} \]
      4. associate-*r*70.0%

        \[\leadsto \sqrt{\frac{{\color{blue}{\left(\left(2 \cdot n\right) \cdot \pi\right)}}^{\left(1 - k\right)}}{k}} \]
    5. Simplified70.0%

      \[\leadsto \color{blue}{\sqrt{\frac{{\left(\left(2 \cdot n\right) \cdot \pi\right)}^{\left(1 - k\right)}}{k}}} \]
    6. Taylor expanded in k around 0 70.0%

      \[\leadsto \sqrt{\color{blue}{2 \cdot \frac{n \cdot \pi}{k}}} \]
    7. Step-by-step derivation
      1. associate-/l*70.0%

        \[\leadsto \sqrt{2 \cdot \color{blue}{\frac{n}{\frac{k}{\pi}}}} \]
    8. Simplified70.0%

      \[\leadsto \sqrt{\color{blue}{2 \cdot \frac{n}{\frac{k}{\pi}}}} \]
    9. Taylor expanded in n around 0 70.0%

      \[\leadsto \sqrt{2 \cdot \color{blue}{\frac{n \cdot \pi}{k}}} \]
    10. Step-by-step derivation
      1. associate-/l*70.0%

        \[\leadsto \sqrt{2 \cdot \color{blue}{\frac{n}{\frac{k}{\pi}}}} \]
      2. *-rgt-identity70.0%

        \[\leadsto \sqrt{2 \cdot \frac{\color{blue}{n \cdot 1}}{\frac{k}{\pi}}} \]
      3. associate-*r/69.9%

        \[\leadsto \sqrt{2 \cdot \color{blue}{\left(n \cdot \frac{1}{\frac{k}{\pi}}\right)}} \]
      4. associate-/r/70.0%

        \[\leadsto \sqrt{2 \cdot \left(n \cdot \color{blue}{\left(\frac{1}{k} \cdot \pi\right)}\right)} \]
      5. associate-*l/70.0%

        \[\leadsto \sqrt{2 \cdot \left(n \cdot \color{blue}{\frac{1 \cdot \pi}{k}}\right)} \]
      6. *-lft-identity70.0%

        \[\leadsto \sqrt{2 \cdot \left(n \cdot \frac{\color{blue}{\pi}}{k}\right)} \]
    11. Simplified70.0%

      \[\leadsto \sqrt{2 \cdot \color{blue}{\left(n \cdot \frac{\pi}{k}\right)}} \]
    12. Step-by-step derivation
      1. pow1/270.0%

        \[\leadsto \color{blue}{{\left(2 \cdot \left(n \cdot \frac{\pi}{k}\right)\right)}^{0.5}} \]
      2. associate-*r*70.0%

        \[\leadsto {\color{blue}{\left(\left(2 \cdot n\right) \cdot \frac{\pi}{k}\right)}}^{0.5} \]
      3. *-commutative70.0%

        \[\leadsto {\left(\color{blue}{\left(n \cdot 2\right)} \cdot \frac{\pi}{k}\right)}^{0.5} \]
      4. unpow-prod-down99.3%

        \[\leadsto \color{blue}{{\left(n \cdot 2\right)}^{0.5} \cdot {\left(\frac{\pi}{k}\right)}^{0.5}} \]
      5. pow1/299.3%

        \[\leadsto \color{blue}{\sqrt{n \cdot 2}} \cdot {\left(\frac{\pi}{k}\right)}^{0.5} \]
      6. *-commutative99.3%

        \[\leadsto \sqrt{\color{blue}{2 \cdot n}} \cdot {\left(\frac{\pi}{k}\right)}^{0.5} \]
      7. pow1/299.3%

        \[\leadsto \sqrt{2 \cdot n} \cdot \color{blue}{\sqrt{\frac{\pi}{k}}} \]
    13. Applied egg-rr99.3%

      \[\leadsto \color{blue}{\sqrt{2 \cdot n} \cdot \sqrt{\frac{\pi}{k}}} \]
    14. Step-by-step derivation
      1. rem-log-exp7.0%

        \[\leadsto \sqrt{2 \cdot \color{blue}{\log \left(e^{n}\right)}} \cdot \sqrt{\frac{\pi}{k}} \]
      2. log-pow7.1%

        \[\leadsto \sqrt{\color{blue}{\log \left({\left(e^{n}\right)}^{2}\right)}} \cdot \sqrt{\frac{\pi}{k}} \]
      3. unpow27.1%

        \[\leadsto \sqrt{\log \color{blue}{\left(e^{n} \cdot e^{n}\right)}} \cdot \sqrt{\frac{\pi}{k}} \]
      4. log-prod7.0%

        \[\leadsto \sqrt{\color{blue}{\log \left(e^{n}\right) + \log \left(e^{n}\right)}} \cdot \sqrt{\frac{\pi}{k}} \]
      5. rem-log-exp15.0%

        \[\leadsto \sqrt{\color{blue}{n} + \log \left(e^{n}\right)} \cdot \sqrt{\frac{\pi}{k}} \]
      6. rem-log-exp99.3%

        \[\leadsto \sqrt{n + \color{blue}{n}} \cdot \sqrt{\frac{\pi}{k}} \]
    15. Simplified99.3%

      \[\leadsto \color{blue}{\sqrt{n + n} \cdot \sqrt{\frac{\pi}{k}}} \]

    if 9.99999999999999908e-22 < k

    1. Initial program 99.8%

      \[\frac{1}{\sqrt{k}} \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(\frac{1 - k}{2}\right)} \]
    2. Step-by-step derivation
      1. *-commutative99.8%

        \[\leadsto \color{blue}{{\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(\frac{1 - k}{2}\right)} \cdot \frac{1}{\sqrt{k}}} \]
      2. *-commutative99.8%

        \[\leadsto {\left(\color{blue}{\left(\pi \cdot 2\right)} \cdot n\right)}^{\left(\frac{1 - k}{2}\right)} \cdot \frac{1}{\sqrt{k}} \]
      3. associate-*r*99.8%

        \[\leadsto {\color{blue}{\left(\pi \cdot \left(2 \cdot n\right)\right)}}^{\left(\frac{1 - k}{2}\right)} \cdot \frac{1}{\sqrt{k}} \]
      4. div-inv99.8%

        \[\leadsto \color{blue}{\frac{{\left(\pi \cdot \left(2 \cdot n\right)\right)}^{\left(\frac{1 - k}{2}\right)}}{\sqrt{k}}} \]
      5. expm1-log1p-u99.8%

        \[\leadsto \color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\frac{{\left(\pi \cdot \left(2 \cdot n\right)\right)}^{\left(\frac{1 - k}{2}\right)}}{\sqrt{k}}\right)\right)} \]
      6. expm1-udef97.5%

        \[\leadsto \color{blue}{e^{\mathsf{log1p}\left(\frac{{\left(\pi \cdot \left(2 \cdot n\right)\right)}^{\left(\frac{1 - k}{2}\right)}}{\sqrt{k}}\right)} - 1} \]
    3. Applied egg-rr97.5%

      \[\leadsto \color{blue}{e^{\mathsf{log1p}\left(\sqrt{\frac{{\left(2 \cdot \left(\pi \cdot n\right)\right)}^{\left(1 - k\right)}}{k}}\right)} - 1} \]
    4. Step-by-step derivation
      1. expm1-def99.8%

        \[\leadsto \color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\sqrt{\frac{{\left(2 \cdot \left(\pi \cdot n\right)\right)}^{\left(1 - k\right)}}{k}}\right)\right)} \]
      2. expm1-log1p99.8%

        \[\leadsto \color{blue}{\sqrt{\frac{{\left(2 \cdot \left(\pi \cdot n\right)\right)}^{\left(1 - k\right)}}{k}}} \]
      3. *-commutative99.8%

        \[\leadsto \sqrt{\frac{{\left(2 \cdot \color{blue}{\left(n \cdot \pi\right)}\right)}^{\left(1 - k\right)}}{k}} \]
      4. associate-*r*99.8%

        \[\leadsto \sqrt{\frac{{\color{blue}{\left(\left(2 \cdot n\right) \cdot \pi\right)}}^{\left(1 - k\right)}}{k}} \]
    5. Simplified99.8%

      \[\leadsto \color{blue}{\sqrt{\frac{{\left(\left(2 \cdot n\right) \cdot \pi\right)}^{\left(1 - k\right)}}{k}}} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification99.6%

    \[\leadsto \begin{array}{l} \mathbf{if}\;k \leq 10^{-21}:\\ \;\;\;\;\sqrt{n + n} \cdot \sqrt{\frac{\pi}{k}}\\ \mathbf{else}:\\ \;\;\;\;\sqrt{\frac{{\left(\pi \cdot \left(2 \cdot n\right)\right)}^{\left(1 - k\right)}}{k}}\\ \end{array} \]

Alternative 6: 99.5% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \frac{{\left(\pi \cdot \left(2 \cdot n\right)\right)}^{\left(\frac{1 - k}{2}\right)}}{\sqrt{k}} \end{array} \]
(FPCore (k n)
 :precision binary64
 (/ (pow (* PI (* 2.0 n)) (/ (- 1.0 k) 2.0)) (sqrt k)))
double code(double k, double n) {
	return pow((((double) M_PI) * (2.0 * n)), ((1.0 - k) / 2.0)) / sqrt(k);
}
public static double code(double k, double n) {
	return Math.pow((Math.PI * (2.0 * n)), ((1.0 - k) / 2.0)) / Math.sqrt(k);
}
def code(k, n):
	return math.pow((math.pi * (2.0 * n)), ((1.0 - k) / 2.0)) / math.sqrt(k)
function code(k, n)
	return Float64((Float64(pi * Float64(2.0 * n)) ^ Float64(Float64(1.0 - k) / 2.0)) / sqrt(k))
end
function tmp = code(k, n)
	tmp = ((pi * (2.0 * n)) ^ ((1.0 - k) / 2.0)) / sqrt(k);
end
code[k_, n_] := N[(N[Power[N[(Pi * N[(2.0 * n), $MachinePrecision]), $MachinePrecision], N[(N[(1.0 - k), $MachinePrecision] / 2.0), $MachinePrecision]], $MachinePrecision] / N[Sqrt[k], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{{\left(\pi \cdot \left(2 \cdot n\right)\right)}^{\left(\frac{1 - k}{2}\right)}}{\sqrt{k}}
\end{array}
Derivation
  1. Initial program 99.5%

    \[\frac{1}{\sqrt{k}} \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(\frac{1 - k}{2}\right)} \]
  2. Step-by-step derivation
    1. associate-*l/99.6%

      \[\leadsto \color{blue}{\frac{1 \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(\frac{1 - k}{2}\right)}}{\sqrt{k}}} \]
    2. *-lft-identity99.6%

      \[\leadsto \frac{\color{blue}{{\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(\frac{1 - k}{2}\right)}}}{\sqrt{k}} \]
    3. *-commutative99.6%

      \[\leadsto \frac{{\left(\color{blue}{\left(\pi \cdot 2\right)} \cdot n\right)}^{\left(\frac{1 - k}{2}\right)}}{\sqrt{k}} \]
    4. associate-*l*99.6%

      \[\leadsto \frac{{\color{blue}{\left(\pi \cdot \left(2 \cdot n\right)\right)}}^{\left(\frac{1 - k}{2}\right)}}{\sqrt{k}} \]
  3. Simplified99.6%

    \[\leadsto \color{blue}{\frac{{\left(\pi \cdot \left(2 \cdot n\right)\right)}^{\left(\frac{1 - k}{2}\right)}}{\sqrt{k}}} \]
  4. Final simplification99.6%

    \[\leadsto \frac{{\left(\pi \cdot \left(2 \cdot n\right)\right)}^{\left(\frac{1 - k}{2}\right)}}{\sqrt{k}} \]

Alternative 7: 49.6% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;k \leq 4.2 \cdot 10^{+223}:\\ \;\;\;\;\sqrt{n + n} \cdot \sqrt{\frac{\pi}{k}}\\ \mathbf{else}:\\ \;\;\;\;\sqrt[3]{{\left(2 \cdot \left(n \cdot \frac{\pi}{k}\right)\right)}^{1.5}}\\ \end{array} \end{array} \]
(FPCore (k n)
 :precision binary64
 (if (<= k 4.2e+223)
   (* (sqrt (+ n n)) (sqrt (/ PI k)))
   (cbrt (pow (* 2.0 (* n (/ PI k))) 1.5))))
double code(double k, double n) {
	double tmp;
	if (k <= 4.2e+223) {
		tmp = sqrt((n + n)) * sqrt((((double) M_PI) / k));
	} else {
		tmp = cbrt(pow((2.0 * (n * (((double) M_PI) / k))), 1.5));
	}
	return tmp;
}
public static double code(double k, double n) {
	double tmp;
	if (k <= 4.2e+223) {
		tmp = Math.sqrt((n + n)) * Math.sqrt((Math.PI / k));
	} else {
		tmp = Math.cbrt(Math.pow((2.0 * (n * (Math.PI / k))), 1.5));
	}
	return tmp;
}
function code(k, n)
	tmp = 0.0
	if (k <= 4.2e+223)
		tmp = Float64(sqrt(Float64(n + n)) * sqrt(Float64(pi / k)));
	else
		tmp = cbrt((Float64(2.0 * Float64(n * Float64(pi / k))) ^ 1.5));
	end
	return tmp
end
code[k_, n_] := If[LessEqual[k, 4.2e+223], N[(N[Sqrt[N[(n + n), $MachinePrecision]], $MachinePrecision] * N[Sqrt[N[(Pi / k), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], N[Power[N[Power[N[(2.0 * N[(n * N[(Pi / k), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], 1.5], $MachinePrecision], 1/3], $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;k \leq 4.2 \cdot 10^{+223}:\\
\;\;\;\;\sqrt{n + n} \cdot \sqrt{\frac{\pi}{k}}\\

\mathbf{else}:\\
\;\;\;\;\sqrt[3]{{\left(2 \cdot \left(n \cdot \frac{\pi}{k}\right)\right)}^{1.5}}\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if k < 4.19999999999999981e223

    1. Initial program 99.4%

      \[\frac{1}{\sqrt{k}} \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(\frac{1 - k}{2}\right)} \]
    2. Step-by-step derivation
      1. *-commutative99.4%

        \[\leadsto \color{blue}{{\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(\frac{1 - k}{2}\right)} \cdot \frac{1}{\sqrt{k}}} \]
      2. *-commutative99.4%

        \[\leadsto {\left(\color{blue}{\left(\pi \cdot 2\right)} \cdot n\right)}^{\left(\frac{1 - k}{2}\right)} \cdot \frac{1}{\sqrt{k}} \]
      3. associate-*r*99.4%

        \[\leadsto {\color{blue}{\left(\pi \cdot \left(2 \cdot n\right)\right)}}^{\left(\frac{1 - k}{2}\right)} \cdot \frac{1}{\sqrt{k}} \]
      4. div-inv99.5%

        \[\leadsto \color{blue}{\frac{{\left(\pi \cdot \left(2 \cdot n\right)\right)}^{\left(\frac{1 - k}{2}\right)}}{\sqrt{k}}} \]
      5. expm1-log1p-u96.6%

        \[\leadsto \color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\frac{{\left(\pi \cdot \left(2 \cdot n\right)\right)}^{\left(\frac{1 - k}{2}\right)}}{\sqrt{k}}\right)\right)} \]
      6. expm1-udef81.5%

        \[\leadsto \color{blue}{e^{\mathsf{log1p}\left(\frac{{\left(\pi \cdot \left(2 \cdot n\right)\right)}^{\left(\frac{1 - k}{2}\right)}}{\sqrt{k}}\right)} - 1} \]
    3. Applied egg-rr67.6%

      \[\leadsto \color{blue}{e^{\mathsf{log1p}\left(\sqrt{\frac{{\left(2 \cdot \left(\pi \cdot n\right)\right)}^{\left(1 - k\right)}}{k}}\right)} - 1} \]
    4. Step-by-step derivation
      1. expm1-def82.8%

        \[\leadsto \color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\sqrt{\frac{{\left(2 \cdot \left(\pi \cdot n\right)\right)}^{\left(1 - k\right)}}{k}}\right)\right)} \]
      2. expm1-log1p84.2%

        \[\leadsto \color{blue}{\sqrt{\frac{{\left(2 \cdot \left(\pi \cdot n\right)\right)}^{\left(1 - k\right)}}{k}}} \]
      3. *-commutative84.2%

        \[\leadsto \sqrt{\frac{{\left(2 \cdot \color{blue}{\left(n \cdot \pi\right)}\right)}^{\left(1 - k\right)}}{k}} \]
      4. associate-*r*84.2%

        \[\leadsto \sqrt{\frac{{\color{blue}{\left(\left(2 \cdot n\right) \cdot \pi\right)}}^{\left(1 - k\right)}}{k}} \]
    5. Simplified84.2%

      \[\leadsto \color{blue}{\sqrt{\frac{{\left(\left(2 \cdot n\right) \cdot \pi\right)}^{\left(1 - k\right)}}{k}}} \]
    6. Taylor expanded in k around 0 39.9%

      \[\leadsto \sqrt{\color{blue}{2 \cdot \frac{n \cdot \pi}{k}}} \]
    7. Step-by-step derivation
      1. associate-/l*39.9%

        \[\leadsto \sqrt{2 \cdot \color{blue}{\frac{n}{\frac{k}{\pi}}}} \]
    8. Simplified39.9%

      \[\leadsto \sqrt{\color{blue}{2 \cdot \frac{n}{\frac{k}{\pi}}}} \]
    9. Taylor expanded in n around 0 39.9%

      \[\leadsto \sqrt{2 \cdot \color{blue}{\frac{n \cdot \pi}{k}}} \]
    10. Step-by-step derivation
      1. associate-/l*39.9%

        \[\leadsto \sqrt{2 \cdot \color{blue}{\frac{n}{\frac{k}{\pi}}}} \]
      2. *-rgt-identity39.9%

        \[\leadsto \sqrt{2 \cdot \frac{\color{blue}{n \cdot 1}}{\frac{k}{\pi}}} \]
      3. associate-*r/39.8%

        \[\leadsto \sqrt{2 \cdot \color{blue}{\left(n \cdot \frac{1}{\frac{k}{\pi}}\right)}} \]
      4. associate-/r/39.9%

        \[\leadsto \sqrt{2 \cdot \left(n \cdot \color{blue}{\left(\frac{1}{k} \cdot \pi\right)}\right)} \]
      5. associate-*l/39.9%

        \[\leadsto \sqrt{2 \cdot \left(n \cdot \color{blue}{\frac{1 \cdot \pi}{k}}\right)} \]
      6. *-lft-identity39.9%

        \[\leadsto \sqrt{2 \cdot \left(n \cdot \frac{\color{blue}{\pi}}{k}\right)} \]
    11. Simplified39.9%

      \[\leadsto \sqrt{2 \cdot \color{blue}{\left(n \cdot \frac{\pi}{k}\right)}} \]
    12. Step-by-step derivation
      1. pow1/239.9%

        \[\leadsto \color{blue}{{\left(2 \cdot \left(n \cdot \frac{\pi}{k}\right)\right)}^{0.5}} \]
      2. associate-*r*39.9%

        \[\leadsto {\color{blue}{\left(\left(2 \cdot n\right) \cdot \frac{\pi}{k}\right)}}^{0.5} \]
      3. *-commutative39.9%

        \[\leadsto {\left(\color{blue}{\left(n \cdot 2\right)} \cdot \frac{\pi}{k}\right)}^{0.5} \]
      4. unpow-prod-down55.1%

        \[\leadsto \color{blue}{{\left(n \cdot 2\right)}^{0.5} \cdot {\left(\frac{\pi}{k}\right)}^{0.5}} \]
      5. pow1/255.1%

        \[\leadsto \color{blue}{\sqrt{n \cdot 2}} \cdot {\left(\frac{\pi}{k}\right)}^{0.5} \]
      6. *-commutative55.1%

        \[\leadsto \sqrt{\color{blue}{2 \cdot n}} \cdot {\left(\frac{\pi}{k}\right)}^{0.5} \]
      7. pow1/255.1%

        \[\leadsto \sqrt{2 \cdot n} \cdot \color{blue}{\sqrt{\frac{\pi}{k}}} \]
    13. Applied egg-rr55.1%

      \[\leadsto \color{blue}{\sqrt{2 \cdot n} \cdot \sqrt{\frac{\pi}{k}}} \]
    14. Step-by-step derivation
      1. rem-log-exp4.5%

        \[\leadsto \sqrt{2 \cdot \color{blue}{\log \left(e^{n}\right)}} \cdot \sqrt{\frac{\pi}{k}} \]
      2. log-pow4.5%

        \[\leadsto \sqrt{\color{blue}{\log \left({\left(e^{n}\right)}^{2}\right)}} \cdot \sqrt{\frac{\pi}{k}} \]
      3. unpow24.5%

        \[\leadsto \sqrt{\log \color{blue}{\left(e^{n} \cdot e^{n}\right)}} \cdot \sqrt{\frac{\pi}{k}} \]
      4. log-prod4.5%

        \[\leadsto \sqrt{\color{blue}{\log \left(e^{n}\right) + \log \left(e^{n}\right)}} \cdot \sqrt{\frac{\pi}{k}} \]
      5. rem-log-exp9.1%

        \[\leadsto \sqrt{\color{blue}{n} + \log \left(e^{n}\right)} \cdot \sqrt{\frac{\pi}{k}} \]
      6. rem-log-exp55.1%

        \[\leadsto \sqrt{n + \color{blue}{n}} \cdot \sqrt{\frac{\pi}{k}} \]
    15. Simplified55.1%

      \[\leadsto \color{blue}{\sqrt{n + n} \cdot \sqrt{\frac{\pi}{k}}} \]

    if 4.19999999999999981e223 < k

    1. Initial program 100.0%

      \[\frac{1}{\sqrt{k}} \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(\frac{1 - k}{2}\right)} \]
    2. Step-by-step derivation
      1. *-commutative100.0%

        \[\leadsto \color{blue}{{\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(\frac{1 - k}{2}\right)} \cdot \frac{1}{\sqrt{k}}} \]
      2. *-commutative100.0%

        \[\leadsto {\left(\color{blue}{\left(\pi \cdot 2\right)} \cdot n\right)}^{\left(\frac{1 - k}{2}\right)} \cdot \frac{1}{\sqrt{k}} \]
      3. associate-*r*100.0%

        \[\leadsto {\color{blue}{\left(\pi \cdot \left(2 \cdot n\right)\right)}}^{\left(\frac{1 - k}{2}\right)} \cdot \frac{1}{\sqrt{k}} \]
      4. div-inv100.0%

        \[\leadsto \color{blue}{\frac{{\left(\pi \cdot \left(2 \cdot n\right)\right)}^{\left(\frac{1 - k}{2}\right)}}{\sqrt{k}}} \]
      5. expm1-log1p-u100.0%

        \[\leadsto \color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\frac{{\left(\pi \cdot \left(2 \cdot n\right)\right)}^{\left(\frac{1 - k}{2}\right)}}{\sqrt{k}}\right)\right)} \]
      6. expm1-udef100.0%

        \[\leadsto \color{blue}{e^{\mathsf{log1p}\left(\frac{{\left(\pi \cdot \left(2 \cdot n\right)\right)}^{\left(\frac{1 - k}{2}\right)}}{\sqrt{k}}\right)} - 1} \]
    3. Applied egg-rr100.0%

      \[\leadsto \color{blue}{e^{\mathsf{log1p}\left(\sqrt{\frac{{\left(2 \cdot \left(\pi \cdot n\right)\right)}^{\left(1 - k\right)}}{k}}\right)} - 1} \]
    4. Step-by-step derivation
      1. expm1-def100.0%

        \[\leadsto \color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\sqrt{\frac{{\left(2 \cdot \left(\pi \cdot n\right)\right)}^{\left(1 - k\right)}}{k}}\right)\right)} \]
      2. expm1-log1p100.0%

        \[\leadsto \color{blue}{\sqrt{\frac{{\left(2 \cdot \left(\pi \cdot n\right)\right)}^{\left(1 - k\right)}}{k}}} \]
      3. *-commutative100.0%

        \[\leadsto \sqrt{\frac{{\left(2 \cdot \color{blue}{\left(n \cdot \pi\right)}\right)}^{\left(1 - k\right)}}{k}} \]
      4. associate-*r*100.0%

        \[\leadsto \sqrt{\frac{{\color{blue}{\left(\left(2 \cdot n\right) \cdot \pi\right)}}^{\left(1 - k\right)}}{k}} \]
    5. Simplified100.0%

      \[\leadsto \color{blue}{\sqrt{\frac{{\left(\left(2 \cdot n\right) \cdot \pi\right)}^{\left(1 - k\right)}}{k}}} \]
    6. Taylor expanded in k around 0 2.7%

      \[\leadsto \sqrt{\color{blue}{2 \cdot \frac{n \cdot \pi}{k}}} \]
    7. Step-by-step derivation
      1. associate-/l*2.7%

        \[\leadsto \sqrt{2 \cdot \color{blue}{\frac{n}{\frac{k}{\pi}}}} \]
    8. Simplified2.7%

      \[\leadsto \sqrt{\color{blue}{2 \cdot \frac{n}{\frac{k}{\pi}}}} \]
    9. Taylor expanded in n around 0 2.7%

      \[\leadsto \sqrt{2 \cdot \color{blue}{\frac{n \cdot \pi}{k}}} \]
    10. Step-by-step derivation
      1. associate-/l*2.7%

        \[\leadsto \sqrt{2 \cdot \color{blue}{\frac{n}{\frac{k}{\pi}}}} \]
      2. *-rgt-identity2.7%

        \[\leadsto \sqrt{2 \cdot \frac{\color{blue}{n \cdot 1}}{\frac{k}{\pi}}} \]
      3. associate-*r/2.7%

        \[\leadsto \sqrt{2 \cdot \color{blue}{\left(n \cdot \frac{1}{\frac{k}{\pi}}\right)}} \]
      4. associate-/r/2.7%

        \[\leadsto \sqrt{2 \cdot \left(n \cdot \color{blue}{\left(\frac{1}{k} \cdot \pi\right)}\right)} \]
      5. associate-*l/2.7%

        \[\leadsto \sqrt{2 \cdot \left(n \cdot \color{blue}{\frac{1 \cdot \pi}{k}}\right)} \]
      6. *-lft-identity2.7%

        \[\leadsto \sqrt{2 \cdot \left(n \cdot \frac{\color{blue}{\pi}}{k}\right)} \]
    11. Simplified2.7%

      \[\leadsto \sqrt{2 \cdot \color{blue}{\left(n \cdot \frac{\pi}{k}\right)}} \]
    12. Step-by-step derivation
      1. clear-num2.7%

        \[\leadsto \sqrt{2 \cdot \left(n \cdot \color{blue}{\frac{1}{\frac{k}{\pi}}}\right)} \]
      2. un-div-inv2.7%

        \[\leadsto \sqrt{2 \cdot \left(n \cdot \frac{1}{\color{blue}{k \cdot \frac{1}{\pi}}}\right)} \]
      3. div-inv2.7%

        \[\leadsto \sqrt{2 \cdot \color{blue}{\frac{n}{k \cdot \frac{1}{\pi}}}} \]
      4. add-cbrt-cube15.6%

        \[\leadsto \color{blue}{\sqrt[3]{\left(\sqrt{2 \cdot \frac{n}{k \cdot \frac{1}{\pi}}} \cdot \sqrt{2 \cdot \frac{n}{k \cdot \frac{1}{\pi}}}\right) \cdot \sqrt{2 \cdot \frac{n}{k \cdot \frac{1}{\pi}}}}} \]
      5. add-sqr-sqrt15.6%

        \[\leadsto \sqrt[3]{\color{blue}{\left(2 \cdot \frac{n}{k \cdot \frac{1}{\pi}}\right)} \cdot \sqrt{2 \cdot \frac{n}{k \cdot \frac{1}{\pi}}}} \]
      6. div-inv15.6%

        \[\leadsto \sqrt[3]{\left(2 \cdot \color{blue}{\left(n \cdot \frac{1}{k \cdot \frac{1}{\pi}}\right)}\right) \cdot \sqrt{2 \cdot \frac{n}{k \cdot \frac{1}{\pi}}}} \]
      7. un-div-inv15.6%

        \[\leadsto \sqrt[3]{\left(2 \cdot \left(n \cdot \frac{1}{\color{blue}{\frac{k}{\pi}}}\right)\right) \cdot \sqrt{2 \cdot \frac{n}{k \cdot \frac{1}{\pi}}}} \]
      8. clear-num15.6%

        \[\leadsto \sqrt[3]{\left(2 \cdot \left(n \cdot \color{blue}{\frac{\pi}{k}}\right)\right) \cdot \sqrt{2 \cdot \frac{n}{k \cdot \frac{1}{\pi}}}} \]
      9. pow115.6%

        \[\leadsto \sqrt[3]{\color{blue}{{\left(2 \cdot \left(n \cdot \frac{\pi}{k}\right)\right)}^{1}} \cdot \sqrt{2 \cdot \frac{n}{k \cdot \frac{1}{\pi}}}} \]
      10. pow1/215.6%

        \[\leadsto \sqrt[3]{{\left(2 \cdot \left(n \cdot \frac{\pi}{k}\right)\right)}^{1} \cdot \color{blue}{{\left(2 \cdot \frac{n}{k \cdot \frac{1}{\pi}}\right)}^{0.5}}} \]
    13. Applied egg-rr15.6%

      \[\leadsto \color{blue}{\sqrt[3]{{\left(2 \cdot \left(n \cdot \frac{\pi}{k}\right)\right)}^{1.5}}} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification49.4%

    \[\leadsto \begin{array}{l} \mathbf{if}\;k \leq 4.2 \cdot 10^{+223}:\\ \;\;\;\;\sqrt{n + n} \cdot \sqrt{\frac{\pi}{k}}\\ \mathbf{else}:\\ \;\;\;\;\sqrt[3]{{\left(2 \cdot \left(n \cdot \frac{\pi}{k}\right)\right)}^{1.5}}\\ \end{array} \]

Alternative 8: 48.6% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \sqrt{n + n} \cdot \sqrt{\frac{\pi}{k}} \end{array} \]
(FPCore (k n) :precision binary64 (* (sqrt (+ n n)) (sqrt (/ PI k))))
double code(double k, double n) {
	return sqrt((n + n)) * sqrt((((double) M_PI) / k));
}
public static double code(double k, double n) {
	return Math.sqrt((n + n)) * Math.sqrt((Math.PI / k));
}
def code(k, n):
	return math.sqrt((n + n)) * math.sqrt((math.pi / k))
function code(k, n)
	return Float64(sqrt(Float64(n + n)) * sqrt(Float64(pi / k)))
end
function tmp = code(k, n)
	tmp = sqrt((n + n)) * sqrt((pi / k));
end
code[k_, n_] := N[(N[Sqrt[N[(n + n), $MachinePrecision]], $MachinePrecision] * N[Sqrt[N[(Pi / k), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\sqrt{n + n} \cdot \sqrt{\frac{\pi}{k}}
\end{array}
Derivation
  1. Initial program 99.5%

    \[\frac{1}{\sqrt{k}} \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(\frac{1 - k}{2}\right)} \]
  2. Step-by-step derivation
    1. *-commutative99.5%

      \[\leadsto \color{blue}{{\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(\frac{1 - k}{2}\right)} \cdot \frac{1}{\sqrt{k}}} \]
    2. *-commutative99.5%

      \[\leadsto {\left(\color{blue}{\left(\pi \cdot 2\right)} \cdot n\right)}^{\left(\frac{1 - k}{2}\right)} \cdot \frac{1}{\sqrt{k}} \]
    3. associate-*r*99.5%

      \[\leadsto {\color{blue}{\left(\pi \cdot \left(2 \cdot n\right)\right)}}^{\left(\frac{1 - k}{2}\right)} \cdot \frac{1}{\sqrt{k}} \]
    4. div-inv99.6%

      \[\leadsto \color{blue}{\frac{{\left(\pi \cdot \left(2 \cdot n\right)\right)}^{\left(\frac{1 - k}{2}\right)}}{\sqrt{k}}} \]
    5. expm1-log1p-u97.1%

      \[\leadsto \color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\frac{{\left(\pi \cdot \left(2 \cdot n\right)\right)}^{\left(\frac{1 - k}{2}\right)}}{\sqrt{k}}\right)\right)} \]
    6. expm1-udef84.2%

      \[\leadsto \color{blue}{e^{\mathsf{log1p}\left(\frac{{\left(\pi \cdot \left(2 \cdot n\right)\right)}^{\left(\frac{1 - k}{2}\right)}}{\sqrt{k}}\right)} - 1} \]
  3. Applied egg-rr72.3%

    \[\leadsto \color{blue}{e^{\mathsf{log1p}\left(\sqrt{\frac{{\left(2 \cdot \left(\pi \cdot n\right)\right)}^{\left(1 - k\right)}}{k}}\right)} - 1} \]
  4. Step-by-step derivation
    1. expm1-def85.3%

      \[\leadsto \color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\sqrt{\frac{{\left(2 \cdot \left(\pi \cdot n\right)\right)}^{\left(1 - k\right)}}{k}}\right)\right)} \]
    2. expm1-log1p86.5%

      \[\leadsto \color{blue}{\sqrt{\frac{{\left(2 \cdot \left(\pi \cdot n\right)\right)}^{\left(1 - k\right)}}{k}}} \]
    3. *-commutative86.5%

      \[\leadsto \sqrt{\frac{{\left(2 \cdot \color{blue}{\left(n \cdot \pi\right)}\right)}^{\left(1 - k\right)}}{k}} \]
    4. associate-*r*86.5%

      \[\leadsto \sqrt{\frac{{\color{blue}{\left(\left(2 \cdot n\right) \cdot \pi\right)}}^{\left(1 - k\right)}}{k}} \]
  5. Simplified86.5%

    \[\leadsto \color{blue}{\sqrt{\frac{{\left(\left(2 \cdot n\right) \cdot \pi\right)}^{\left(1 - k\right)}}{k}}} \]
  6. Taylor expanded in k around 0 34.5%

    \[\leadsto \sqrt{\color{blue}{2 \cdot \frac{n \cdot \pi}{k}}} \]
  7. Step-by-step derivation
    1. associate-/l*34.5%

      \[\leadsto \sqrt{2 \cdot \color{blue}{\frac{n}{\frac{k}{\pi}}}} \]
  8. Simplified34.5%

    \[\leadsto \sqrt{\color{blue}{2 \cdot \frac{n}{\frac{k}{\pi}}}} \]
  9. Taylor expanded in n around 0 34.5%

    \[\leadsto \sqrt{2 \cdot \color{blue}{\frac{n \cdot \pi}{k}}} \]
  10. Step-by-step derivation
    1. associate-/l*34.5%

      \[\leadsto \sqrt{2 \cdot \color{blue}{\frac{n}{\frac{k}{\pi}}}} \]
    2. *-rgt-identity34.5%

      \[\leadsto \sqrt{2 \cdot \frac{\color{blue}{n \cdot 1}}{\frac{k}{\pi}}} \]
    3. associate-*r/34.5%

      \[\leadsto \sqrt{2 \cdot \color{blue}{\left(n \cdot \frac{1}{\frac{k}{\pi}}\right)}} \]
    4. associate-/r/34.5%

      \[\leadsto \sqrt{2 \cdot \left(n \cdot \color{blue}{\left(\frac{1}{k} \cdot \pi\right)}\right)} \]
    5. associate-*l/34.5%

      \[\leadsto \sqrt{2 \cdot \left(n \cdot \color{blue}{\frac{1 \cdot \pi}{k}}\right)} \]
    6. *-lft-identity34.5%

      \[\leadsto \sqrt{2 \cdot \left(n \cdot \frac{\color{blue}{\pi}}{k}\right)} \]
  11. Simplified34.5%

    \[\leadsto \sqrt{2 \cdot \color{blue}{\left(n \cdot \frac{\pi}{k}\right)}} \]
  12. Step-by-step derivation
    1. pow1/234.5%

      \[\leadsto \color{blue}{{\left(2 \cdot \left(n \cdot \frac{\pi}{k}\right)\right)}^{0.5}} \]
    2. associate-*r*34.5%

      \[\leadsto {\color{blue}{\left(\left(2 \cdot n\right) \cdot \frac{\pi}{k}\right)}}^{0.5} \]
    3. *-commutative34.5%

      \[\leadsto {\left(\color{blue}{\left(n \cdot 2\right)} \cdot \frac{\pi}{k}\right)}^{0.5} \]
    4. unpow-prod-down47.6%

      \[\leadsto \color{blue}{{\left(n \cdot 2\right)}^{0.5} \cdot {\left(\frac{\pi}{k}\right)}^{0.5}} \]
    5. pow1/247.6%

      \[\leadsto \color{blue}{\sqrt{n \cdot 2}} \cdot {\left(\frac{\pi}{k}\right)}^{0.5} \]
    6. *-commutative47.6%

      \[\leadsto \sqrt{\color{blue}{2 \cdot n}} \cdot {\left(\frac{\pi}{k}\right)}^{0.5} \]
    7. pow1/247.6%

      \[\leadsto \sqrt{2 \cdot n} \cdot \color{blue}{\sqrt{\frac{\pi}{k}}} \]
  13. Applied egg-rr47.6%

    \[\leadsto \color{blue}{\sqrt{2 \cdot n} \cdot \sqrt{\frac{\pi}{k}}} \]
  14. Step-by-step derivation
    1. rem-log-exp4.1%

      \[\leadsto \sqrt{2 \cdot \color{blue}{\log \left(e^{n}\right)}} \cdot \sqrt{\frac{\pi}{k}} \]
    2. log-pow4.1%

      \[\leadsto \sqrt{\color{blue}{\log \left({\left(e^{n}\right)}^{2}\right)}} \cdot \sqrt{\frac{\pi}{k}} \]
    3. unpow24.1%

      \[\leadsto \sqrt{\log \color{blue}{\left(e^{n} \cdot e^{n}\right)}} \cdot \sqrt{\frac{\pi}{k}} \]
    4. log-prod4.1%

      \[\leadsto \sqrt{\color{blue}{\log \left(e^{n}\right) + \log \left(e^{n}\right)}} \cdot \sqrt{\frac{\pi}{k}} \]
    5. rem-log-exp8.0%

      \[\leadsto \sqrt{\color{blue}{n} + \log \left(e^{n}\right)} \cdot \sqrt{\frac{\pi}{k}} \]
    6. rem-log-exp47.6%

      \[\leadsto \sqrt{n + \color{blue}{n}} \cdot \sqrt{\frac{\pi}{k}} \]
  15. Simplified47.6%

    \[\leadsto \color{blue}{\sqrt{n + n} \cdot \sqrt{\frac{\pi}{k}}} \]
  16. Final simplification47.6%

    \[\leadsto \sqrt{n + n} \cdot \sqrt{\frac{\pi}{k}} \]

Alternative 9: 37.6% accurate, 1.5× speedup?

\[\begin{array}{l} \\ \sqrt{2 \cdot \left(n \cdot \left(\pi \cdot \frac{1}{k}\right)\right)} \end{array} \]
(FPCore (k n) :precision binary64 (sqrt (* 2.0 (* n (* PI (/ 1.0 k))))))
double code(double k, double n) {
	return sqrt((2.0 * (n * (((double) M_PI) * (1.0 / k)))));
}
public static double code(double k, double n) {
	return Math.sqrt((2.0 * (n * (Math.PI * (1.0 / k)))));
}
def code(k, n):
	return math.sqrt((2.0 * (n * (math.pi * (1.0 / k)))))
function code(k, n)
	return sqrt(Float64(2.0 * Float64(n * Float64(pi * Float64(1.0 / k)))))
end
function tmp = code(k, n)
	tmp = sqrt((2.0 * (n * (pi * (1.0 / k)))));
end
code[k_, n_] := N[Sqrt[N[(2.0 * N[(n * N[(Pi * N[(1.0 / k), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]
\begin{array}{l}

\\
\sqrt{2 \cdot \left(n \cdot \left(\pi \cdot \frac{1}{k}\right)\right)}
\end{array}
Derivation
  1. Initial program 99.5%

    \[\frac{1}{\sqrt{k}} \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(\frac{1 - k}{2}\right)} \]
  2. Step-by-step derivation
    1. *-commutative99.5%

      \[\leadsto \color{blue}{{\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(\frac{1 - k}{2}\right)} \cdot \frac{1}{\sqrt{k}}} \]
    2. *-commutative99.5%

      \[\leadsto {\left(\color{blue}{\left(\pi \cdot 2\right)} \cdot n\right)}^{\left(\frac{1 - k}{2}\right)} \cdot \frac{1}{\sqrt{k}} \]
    3. associate-*r*99.5%

      \[\leadsto {\color{blue}{\left(\pi \cdot \left(2 \cdot n\right)\right)}}^{\left(\frac{1 - k}{2}\right)} \cdot \frac{1}{\sqrt{k}} \]
    4. div-inv99.6%

      \[\leadsto \color{blue}{\frac{{\left(\pi \cdot \left(2 \cdot n\right)\right)}^{\left(\frac{1 - k}{2}\right)}}{\sqrt{k}}} \]
    5. expm1-log1p-u97.1%

      \[\leadsto \color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\frac{{\left(\pi \cdot \left(2 \cdot n\right)\right)}^{\left(\frac{1 - k}{2}\right)}}{\sqrt{k}}\right)\right)} \]
    6. expm1-udef84.2%

      \[\leadsto \color{blue}{e^{\mathsf{log1p}\left(\frac{{\left(\pi \cdot \left(2 \cdot n\right)\right)}^{\left(\frac{1 - k}{2}\right)}}{\sqrt{k}}\right)} - 1} \]
  3. Applied egg-rr72.3%

    \[\leadsto \color{blue}{e^{\mathsf{log1p}\left(\sqrt{\frac{{\left(2 \cdot \left(\pi \cdot n\right)\right)}^{\left(1 - k\right)}}{k}}\right)} - 1} \]
  4. Step-by-step derivation
    1. expm1-def85.3%

      \[\leadsto \color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\sqrt{\frac{{\left(2 \cdot \left(\pi \cdot n\right)\right)}^{\left(1 - k\right)}}{k}}\right)\right)} \]
    2. expm1-log1p86.5%

      \[\leadsto \color{blue}{\sqrt{\frac{{\left(2 \cdot \left(\pi \cdot n\right)\right)}^{\left(1 - k\right)}}{k}}} \]
    3. *-commutative86.5%

      \[\leadsto \sqrt{\frac{{\left(2 \cdot \color{blue}{\left(n \cdot \pi\right)}\right)}^{\left(1 - k\right)}}{k}} \]
    4. associate-*r*86.5%

      \[\leadsto \sqrt{\frac{{\color{blue}{\left(\left(2 \cdot n\right) \cdot \pi\right)}}^{\left(1 - k\right)}}{k}} \]
  5. Simplified86.5%

    \[\leadsto \color{blue}{\sqrt{\frac{{\left(\left(2 \cdot n\right) \cdot \pi\right)}^{\left(1 - k\right)}}{k}}} \]
  6. Taylor expanded in k around 0 34.5%

    \[\leadsto \sqrt{\color{blue}{2 \cdot \frac{n \cdot \pi}{k}}} \]
  7. Step-by-step derivation
    1. associate-/l*34.5%

      \[\leadsto \sqrt{2 \cdot \color{blue}{\frac{n}{\frac{k}{\pi}}}} \]
  8. Simplified34.5%

    \[\leadsto \sqrt{\color{blue}{2 \cdot \frac{n}{\frac{k}{\pi}}}} \]
  9. Taylor expanded in n around 0 34.5%

    \[\leadsto \sqrt{2 \cdot \color{blue}{\frac{n \cdot \pi}{k}}} \]
  10. Step-by-step derivation
    1. associate-/l*34.5%

      \[\leadsto \sqrt{2 \cdot \color{blue}{\frac{n}{\frac{k}{\pi}}}} \]
    2. *-rgt-identity34.5%

      \[\leadsto \sqrt{2 \cdot \frac{\color{blue}{n \cdot 1}}{\frac{k}{\pi}}} \]
    3. associate-*r/34.5%

      \[\leadsto \sqrt{2 \cdot \color{blue}{\left(n \cdot \frac{1}{\frac{k}{\pi}}\right)}} \]
    4. associate-/r/34.5%

      \[\leadsto \sqrt{2 \cdot \left(n \cdot \color{blue}{\left(\frac{1}{k} \cdot \pi\right)}\right)} \]
    5. associate-*l/34.5%

      \[\leadsto \sqrt{2 \cdot \left(n \cdot \color{blue}{\frac{1 \cdot \pi}{k}}\right)} \]
    6. *-lft-identity34.5%

      \[\leadsto \sqrt{2 \cdot \left(n \cdot \frac{\color{blue}{\pi}}{k}\right)} \]
  11. Simplified34.5%

    \[\leadsto \sqrt{2 \cdot \color{blue}{\left(n \cdot \frac{\pi}{k}\right)}} \]
  12. Step-by-step derivation
    1. div-inv34.5%

      \[\leadsto \sqrt{2 \cdot \left(n \cdot \color{blue}{\left(\pi \cdot \frac{1}{k}\right)}\right)} \]
  13. Applied egg-rr34.5%

    \[\leadsto \sqrt{2 \cdot \left(n \cdot \color{blue}{\left(\pi \cdot \frac{1}{k}\right)}\right)} \]
  14. Final simplification34.5%

    \[\leadsto \sqrt{2 \cdot \left(n \cdot \left(\pi \cdot \frac{1}{k}\right)\right)} \]

Alternative 10: 37.6% accurate, 1.5× speedup?

\[\begin{array}{l} \\ \sqrt{2 \cdot \left(n \cdot \frac{\pi}{k}\right)} \end{array} \]
(FPCore (k n) :precision binary64 (sqrt (* 2.0 (* n (/ PI k)))))
double code(double k, double n) {
	return sqrt((2.0 * (n * (((double) M_PI) / k))));
}
public static double code(double k, double n) {
	return Math.sqrt((2.0 * (n * (Math.PI / k))));
}
def code(k, n):
	return math.sqrt((2.0 * (n * (math.pi / k))))
function code(k, n)
	return sqrt(Float64(2.0 * Float64(n * Float64(pi / k))))
end
function tmp = code(k, n)
	tmp = sqrt((2.0 * (n * (pi / k))));
end
code[k_, n_] := N[Sqrt[N[(2.0 * N[(n * N[(Pi / k), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]
\begin{array}{l}

\\
\sqrt{2 \cdot \left(n \cdot \frac{\pi}{k}\right)}
\end{array}
Derivation
  1. Initial program 99.5%

    \[\frac{1}{\sqrt{k}} \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(\frac{1 - k}{2}\right)} \]
  2. Step-by-step derivation
    1. *-commutative99.5%

      \[\leadsto \color{blue}{{\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(\frac{1 - k}{2}\right)} \cdot \frac{1}{\sqrt{k}}} \]
    2. *-commutative99.5%

      \[\leadsto {\left(\color{blue}{\left(\pi \cdot 2\right)} \cdot n\right)}^{\left(\frac{1 - k}{2}\right)} \cdot \frac{1}{\sqrt{k}} \]
    3. associate-*r*99.5%

      \[\leadsto {\color{blue}{\left(\pi \cdot \left(2 \cdot n\right)\right)}}^{\left(\frac{1 - k}{2}\right)} \cdot \frac{1}{\sqrt{k}} \]
    4. div-inv99.6%

      \[\leadsto \color{blue}{\frac{{\left(\pi \cdot \left(2 \cdot n\right)\right)}^{\left(\frac{1 - k}{2}\right)}}{\sqrt{k}}} \]
    5. expm1-log1p-u97.1%

      \[\leadsto \color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\frac{{\left(\pi \cdot \left(2 \cdot n\right)\right)}^{\left(\frac{1 - k}{2}\right)}}{\sqrt{k}}\right)\right)} \]
    6. expm1-udef84.2%

      \[\leadsto \color{blue}{e^{\mathsf{log1p}\left(\frac{{\left(\pi \cdot \left(2 \cdot n\right)\right)}^{\left(\frac{1 - k}{2}\right)}}{\sqrt{k}}\right)} - 1} \]
  3. Applied egg-rr72.3%

    \[\leadsto \color{blue}{e^{\mathsf{log1p}\left(\sqrt{\frac{{\left(2 \cdot \left(\pi \cdot n\right)\right)}^{\left(1 - k\right)}}{k}}\right)} - 1} \]
  4. Step-by-step derivation
    1. expm1-def85.3%

      \[\leadsto \color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\sqrt{\frac{{\left(2 \cdot \left(\pi \cdot n\right)\right)}^{\left(1 - k\right)}}{k}}\right)\right)} \]
    2. expm1-log1p86.5%

      \[\leadsto \color{blue}{\sqrt{\frac{{\left(2 \cdot \left(\pi \cdot n\right)\right)}^{\left(1 - k\right)}}{k}}} \]
    3. *-commutative86.5%

      \[\leadsto \sqrt{\frac{{\left(2 \cdot \color{blue}{\left(n \cdot \pi\right)}\right)}^{\left(1 - k\right)}}{k}} \]
    4. associate-*r*86.5%

      \[\leadsto \sqrt{\frac{{\color{blue}{\left(\left(2 \cdot n\right) \cdot \pi\right)}}^{\left(1 - k\right)}}{k}} \]
  5. Simplified86.5%

    \[\leadsto \color{blue}{\sqrt{\frac{{\left(\left(2 \cdot n\right) \cdot \pi\right)}^{\left(1 - k\right)}}{k}}} \]
  6. Taylor expanded in k around 0 34.5%

    \[\leadsto \sqrt{\color{blue}{2 \cdot \frac{n \cdot \pi}{k}}} \]
  7. Step-by-step derivation
    1. associate-/l*34.5%

      \[\leadsto \sqrt{2 \cdot \color{blue}{\frac{n}{\frac{k}{\pi}}}} \]
  8. Simplified34.5%

    \[\leadsto \sqrt{\color{blue}{2 \cdot \frac{n}{\frac{k}{\pi}}}} \]
  9. Taylor expanded in n around 0 34.5%

    \[\leadsto \sqrt{2 \cdot \color{blue}{\frac{n \cdot \pi}{k}}} \]
  10. Step-by-step derivation
    1. associate-/l*34.5%

      \[\leadsto \sqrt{2 \cdot \color{blue}{\frac{n}{\frac{k}{\pi}}}} \]
    2. *-rgt-identity34.5%

      \[\leadsto \sqrt{2 \cdot \frac{\color{blue}{n \cdot 1}}{\frac{k}{\pi}}} \]
    3. associate-*r/34.5%

      \[\leadsto \sqrt{2 \cdot \color{blue}{\left(n \cdot \frac{1}{\frac{k}{\pi}}\right)}} \]
    4. associate-/r/34.5%

      \[\leadsto \sqrt{2 \cdot \left(n \cdot \color{blue}{\left(\frac{1}{k} \cdot \pi\right)}\right)} \]
    5. associate-*l/34.5%

      \[\leadsto \sqrt{2 \cdot \left(n \cdot \color{blue}{\frac{1 \cdot \pi}{k}}\right)} \]
    6. *-lft-identity34.5%

      \[\leadsto \sqrt{2 \cdot \left(n \cdot \frac{\color{blue}{\pi}}{k}\right)} \]
  11. Simplified34.5%

    \[\leadsto \sqrt{2 \cdot \color{blue}{\left(n \cdot \frac{\pi}{k}\right)}} \]
  12. Final simplification34.5%

    \[\leadsto \sqrt{2 \cdot \left(n \cdot \frac{\pi}{k}\right)} \]

Alternative 11: 37.6% accurate, 1.5× speedup?

\[\begin{array}{l} \\ \sqrt{\frac{\pi \cdot n}{\frac{k}{2}}} \end{array} \]
(FPCore (k n) :precision binary64 (sqrt (/ (* PI n) (/ k 2.0))))
double code(double k, double n) {
	return sqrt(((((double) M_PI) * n) / (k / 2.0)));
}
public static double code(double k, double n) {
	return Math.sqrt(((Math.PI * n) / (k / 2.0)));
}
def code(k, n):
	return math.sqrt(((math.pi * n) / (k / 2.0)))
function code(k, n)
	return sqrt(Float64(Float64(pi * n) / Float64(k / 2.0)))
end
function tmp = code(k, n)
	tmp = sqrt(((pi * n) / (k / 2.0)));
end
code[k_, n_] := N[Sqrt[N[(N[(Pi * n), $MachinePrecision] / N[(k / 2.0), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]
\begin{array}{l}

\\
\sqrt{\frac{\pi \cdot n}{\frac{k}{2}}}
\end{array}
Derivation
  1. Initial program 99.5%

    \[\frac{1}{\sqrt{k}} \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(\frac{1 - k}{2}\right)} \]
  2. Step-by-step derivation
    1. *-commutative99.5%

      \[\leadsto \color{blue}{{\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(\frac{1 - k}{2}\right)} \cdot \frac{1}{\sqrt{k}}} \]
    2. *-commutative99.5%

      \[\leadsto {\left(\color{blue}{\left(\pi \cdot 2\right)} \cdot n\right)}^{\left(\frac{1 - k}{2}\right)} \cdot \frac{1}{\sqrt{k}} \]
    3. associate-*r*99.5%

      \[\leadsto {\color{blue}{\left(\pi \cdot \left(2 \cdot n\right)\right)}}^{\left(\frac{1 - k}{2}\right)} \cdot \frac{1}{\sqrt{k}} \]
    4. div-inv99.6%

      \[\leadsto \color{blue}{\frac{{\left(\pi \cdot \left(2 \cdot n\right)\right)}^{\left(\frac{1 - k}{2}\right)}}{\sqrt{k}}} \]
    5. expm1-log1p-u97.1%

      \[\leadsto \color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\frac{{\left(\pi \cdot \left(2 \cdot n\right)\right)}^{\left(\frac{1 - k}{2}\right)}}{\sqrt{k}}\right)\right)} \]
    6. expm1-udef84.2%

      \[\leadsto \color{blue}{e^{\mathsf{log1p}\left(\frac{{\left(\pi \cdot \left(2 \cdot n\right)\right)}^{\left(\frac{1 - k}{2}\right)}}{\sqrt{k}}\right)} - 1} \]
  3. Applied egg-rr72.3%

    \[\leadsto \color{blue}{e^{\mathsf{log1p}\left(\sqrt{\frac{{\left(2 \cdot \left(\pi \cdot n\right)\right)}^{\left(1 - k\right)}}{k}}\right)} - 1} \]
  4. Step-by-step derivation
    1. expm1-def85.3%

      \[\leadsto \color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\sqrt{\frac{{\left(2 \cdot \left(\pi \cdot n\right)\right)}^{\left(1 - k\right)}}{k}}\right)\right)} \]
    2. expm1-log1p86.5%

      \[\leadsto \color{blue}{\sqrt{\frac{{\left(2 \cdot \left(\pi \cdot n\right)\right)}^{\left(1 - k\right)}}{k}}} \]
    3. *-commutative86.5%

      \[\leadsto \sqrt{\frac{{\left(2 \cdot \color{blue}{\left(n \cdot \pi\right)}\right)}^{\left(1 - k\right)}}{k}} \]
    4. associate-*r*86.5%

      \[\leadsto \sqrt{\frac{{\color{blue}{\left(\left(2 \cdot n\right) \cdot \pi\right)}}^{\left(1 - k\right)}}{k}} \]
  5. Simplified86.5%

    \[\leadsto \color{blue}{\sqrt{\frac{{\left(\left(2 \cdot n\right) \cdot \pi\right)}^{\left(1 - k\right)}}{k}}} \]
  6. Taylor expanded in k around 0 34.5%

    \[\leadsto \sqrt{\color{blue}{2 \cdot \frac{n \cdot \pi}{k}}} \]
  7. Step-by-step derivation
    1. associate-*r/34.5%

      \[\leadsto \sqrt{\color{blue}{\frac{2 \cdot \left(n \cdot \pi\right)}{k}}} \]
    2. *-commutative34.5%

      \[\leadsto \sqrt{\frac{2 \cdot \color{blue}{\left(\pi \cdot n\right)}}{k}} \]
    3. *-commutative34.5%

      \[\leadsto \sqrt{\frac{\color{blue}{\left(\pi \cdot n\right) \cdot 2}}{k}} \]
    4. associate-/l*34.5%

      \[\leadsto \sqrt{\color{blue}{\frac{\pi \cdot n}{\frac{k}{2}}}} \]
  8. Simplified34.5%

    \[\leadsto \sqrt{\color{blue}{\frac{\pi \cdot n}{\frac{k}{2}}}} \]
  9. Final simplification34.5%

    \[\leadsto \sqrt{\frac{\pi \cdot n}{\frac{k}{2}}} \]

Reproduce

?
herbie shell --seed 2023229 
(FPCore (k n)
  :name "Migdal et al, Equation (51)"
  :precision binary64
  (* (/ 1.0 (sqrt k)) (pow (* (* 2.0 PI) n) (/ (- 1.0 k) 2.0))))