2log (problem 3.3.6)

Percentage Accurate: 23.7% → 99.4%
Time: 12.6s
Alternatives: 9
Speedup: 68.3×

Specification

?
\[N > 1 \land N < 10^{+40}\]
\[\begin{array}{l} \\ \log \left(N + 1\right) - \log N \end{array} \]
(FPCore (N) :precision binary64 (- (log (+ N 1.0)) (log N)))
double code(double N) {
	return log((N + 1.0)) - log(N);
}
real(8) function code(n)
    real(8), intent (in) :: n
    code = log((n + 1.0d0)) - log(n)
end function
public static double code(double N) {
	return Math.log((N + 1.0)) - Math.log(N);
}
def code(N):
	return math.log((N + 1.0)) - math.log(N)
function code(N)
	return Float64(log(Float64(N + 1.0)) - log(N))
end
function tmp = code(N)
	tmp = log((N + 1.0)) - log(N);
end
code[N_] := N[(N[Log[N[(N + 1.0), $MachinePrecision]], $MachinePrecision] - N[Log[N], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\log \left(N + 1\right) - \log N
\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 9 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: 23.7% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \log \left(N + 1\right) - \log N \end{array} \]
(FPCore (N) :precision binary64 (- (log (+ N 1.0)) (log N)))
double code(double N) {
	return log((N + 1.0)) - log(N);
}
real(8) function code(n)
    real(8), intent (in) :: n
    code = log((n + 1.0d0)) - log(n)
end function
public static double code(double N) {
	return Math.log((N + 1.0)) - Math.log(N);
}
def code(N):
	return math.log((N + 1.0)) - math.log(N)
function code(N)
	return Float64(log(Float64(N + 1.0)) - log(N))
end
function tmp = code(N)
	tmp = log((N + 1.0)) - log(N);
end
code[N_] := N[(N[Log[N[(N + 1.0), $MachinePrecision]], $MachinePrecision] - N[Log[N], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\log \left(N + 1\right) - \log N
\end{array}

Alternative 1: 99.4% accurate, 0.7× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;\log \left(N + 1\right) - \log N \leq 0.0006:\\ \;\;\;\;\frac{1 - \frac{\frac{\frac{0.25 + \frac{-0.375}{N}}{N} - 0.3333333333333333}{N} - -0.5}{N}}{N}\\ \mathbf{else}:\\ \;\;\;\;-\log \left(\frac{N}{N + 1}\right)\\ \end{array} \end{array} \]
(FPCore (N)
 :precision binary64
 (if (<= (- (log (+ N 1.0)) (log N)) 0.0006)
   (/
    (-
     1.0
     (/ (- (/ (- (/ (+ 0.25 (/ -0.375 N)) N) 0.3333333333333333) N) -0.5) N))
    N)
   (- (log (/ N (+ N 1.0))))))
double code(double N) {
	double tmp;
	if ((log((N + 1.0)) - log(N)) <= 0.0006) {
		tmp = (1.0 - ((((((0.25 + (-0.375 / N)) / N) - 0.3333333333333333) / N) - -0.5) / N)) / N;
	} else {
		tmp = -log((N / (N + 1.0)));
	}
	return tmp;
}
real(8) function code(n)
    real(8), intent (in) :: n
    real(8) :: tmp
    if ((log((n + 1.0d0)) - log(n)) <= 0.0006d0) then
        tmp = (1.0d0 - ((((((0.25d0 + ((-0.375d0) / n)) / n) - 0.3333333333333333d0) / n) - (-0.5d0)) / n)) / n
    else
        tmp = -log((n / (n + 1.0d0)))
    end if
    code = tmp
end function
public static double code(double N) {
	double tmp;
	if ((Math.log((N + 1.0)) - Math.log(N)) <= 0.0006) {
		tmp = (1.0 - ((((((0.25 + (-0.375 / N)) / N) - 0.3333333333333333) / N) - -0.5) / N)) / N;
	} else {
		tmp = -Math.log((N / (N + 1.0)));
	}
	return tmp;
}
def code(N):
	tmp = 0
	if (math.log((N + 1.0)) - math.log(N)) <= 0.0006:
		tmp = (1.0 - ((((((0.25 + (-0.375 / N)) / N) - 0.3333333333333333) / N) - -0.5) / N)) / N
	else:
		tmp = -math.log((N / (N + 1.0)))
	return tmp
function code(N)
	tmp = 0.0
	if (Float64(log(Float64(N + 1.0)) - log(N)) <= 0.0006)
		tmp = Float64(Float64(1.0 - Float64(Float64(Float64(Float64(Float64(Float64(0.25 + Float64(-0.375 / N)) / N) - 0.3333333333333333) / N) - -0.5) / N)) / N);
	else
		tmp = Float64(-log(Float64(N / Float64(N + 1.0))));
	end
	return tmp
end
function tmp_2 = code(N)
	tmp = 0.0;
	if ((log((N + 1.0)) - log(N)) <= 0.0006)
		tmp = (1.0 - ((((((0.25 + (-0.375 / N)) / N) - 0.3333333333333333) / N) - -0.5) / N)) / N;
	else
		tmp = -log((N / (N + 1.0)));
	end
	tmp_2 = tmp;
end
code[N_] := If[LessEqual[N[(N[Log[N[(N + 1.0), $MachinePrecision]], $MachinePrecision] - N[Log[N], $MachinePrecision]), $MachinePrecision], 0.0006], N[(N[(1.0 - N[(N[(N[(N[(N[(N[(0.25 + N[(-0.375 / N), $MachinePrecision]), $MachinePrecision] / N), $MachinePrecision] - 0.3333333333333333), $MachinePrecision] / N), $MachinePrecision] - -0.5), $MachinePrecision] / N), $MachinePrecision]), $MachinePrecision] / N), $MachinePrecision], (-N[Log[N[(N / N[(N + 1.0), $MachinePrecision]), $MachinePrecision]], $MachinePrecision])]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;\log \left(N + 1\right) - \log N \leq 0.0006:\\
\;\;\;\;\frac{1 - \frac{\frac{\frac{0.25 + \frac{-0.375}{N}}{N} - 0.3333333333333333}{N} - -0.5}{N}}{N}\\

\mathbf{else}:\\
\;\;\;\;-\log \left(\frac{N}{N + 1}\right)\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if (-.f64 (log.f64 (+.f64 N #s(literal 1 binary64))) (log.f64 N)) < 5.99999999999999947e-4

    1. Initial program 16.5%

      \[\log \left(N + 1\right) - \log N \]
    2. Step-by-step derivation
      1. +-commutative16.5%

        \[\leadsto \log \color{blue}{\left(1 + N\right)} - \log N \]
      2. log1p-define16.5%

        \[\leadsto \color{blue}{\mathsf{log1p}\left(N\right)} - \log N \]
    3. Simplified16.5%

      \[\leadsto \color{blue}{\mathsf{log1p}\left(N\right) - \log N} \]
    4. Add Preprocessing
    5. Taylor expanded in N around -inf 99.8%

      \[\leadsto \color{blue}{-1 \cdot \frac{-1 \cdot \frac{-1 \cdot \frac{0.25 \cdot \frac{1}{N} - 0.3333333333333333}{N} - 0.5}{N} - 1}{N}} \]
    6. Step-by-step derivation
      1. mul-1-neg99.8%

        \[\leadsto \color{blue}{-\frac{-1 \cdot \frac{-1 \cdot \frac{0.25 \cdot \frac{1}{N} - 0.3333333333333333}{N} - 0.5}{N} - 1}{N}} \]
      2. distribute-neg-frac299.8%

        \[\leadsto \color{blue}{\frac{-1 \cdot \frac{-1 \cdot \frac{0.25 \cdot \frac{1}{N} - 0.3333333333333333}{N} - 0.5}{N} - 1}{-N}} \]
    7. Simplified99.8%

      \[\leadsto \color{blue}{\frac{-1 - \frac{-0.5 + \frac{0.3333333333333333 + \frac{-0.25}{N}}{N}}{N}}{-N}} \]
    8. Step-by-step derivation
      1. flip-+99.8%

        \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\color{blue}{\frac{0.3333333333333333 \cdot 0.3333333333333333 - \frac{-0.25}{N} \cdot \frac{-0.25}{N}}{0.3333333333333333 - \frac{-0.25}{N}}}}{N}}{N}}{-N} \]
      2. frac-2neg99.8%

        \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\color{blue}{\frac{-\left(0.3333333333333333 \cdot 0.3333333333333333 - \frac{-0.25}{N} \cdot \frac{-0.25}{N}\right)}{-\left(0.3333333333333333 - \frac{-0.25}{N}\right)}}}{N}}{N}}{-N} \]
      3. cancel-sign-sub-inv99.8%

        \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\frac{-\color{blue}{\left(0.3333333333333333 \cdot 0.3333333333333333 + \left(-\frac{-0.25}{N}\right) \cdot \frac{-0.25}{N}\right)}}{-\left(0.3333333333333333 - \frac{-0.25}{N}\right)}}{N}}{N}}{-N} \]
      4. metadata-eval99.8%

        \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\frac{-\left(\color{blue}{0.1111111111111111} + \left(-\frac{-0.25}{N}\right) \cdot \frac{-0.25}{N}\right)}{-\left(0.3333333333333333 - \frac{-0.25}{N}\right)}}{N}}{N}}{-N} \]
      5. frac-2neg99.8%

        \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\frac{-\left(0.1111111111111111 + \left(-\color{blue}{\frac{--0.25}{-N}}\right) \cdot \frac{-0.25}{N}\right)}{-\left(0.3333333333333333 - \frac{-0.25}{N}\right)}}{N}}{N}}{-N} \]
      6. add-sqr-sqrt0.0%

        \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\frac{-\left(0.1111111111111111 + \left(-\frac{--0.25}{\color{blue}{\sqrt{-N} \cdot \sqrt{-N}}}\right) \cdot \frac{-0.25}{N}\right)}{-\left(0.3333333333333333 - \frac{-0.25}{N}\right)}}{N}}{N}}{-N} \]
      7. sqrt-unprod99.8%

        \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\frac{-\left(0.1111111111111111 + \left(-\frac{--0.25}{\color{blue}{\sqrt{\left(-N\right) \cdot \left(-N\right)}}}\right) \cdot \frac{-0.25}{N}\right)}{-\left(0.3333333333333333 - \frac{-0.25}{N}\right)}}{N}}{N}}{-N} \]
      8. sqr-neg99.8%

        \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\frac{-\left(0.1111111111111111 + \left(-\frac{--0.25}{\sqrt{\color{blue}{N \cdot N}}}\right) \cdot \frac{-0.25}{N}\right)}{-\left(0.3333333333333333 - \frac{-0.25}{N}\right)}}{N}}{N}}{-N} \]
      9. sqrt-unprod99.8%

        \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\frac{-\left(0.1111111111111111 + \left(-\frac{--0.25}{\color{blue}{\sqrt{N} \cdot \sqrt{N}}}\right) \cdot \frac{-0.25}{N}\right)}{-\left(0.3333333333333333 - \frac{-0.25}{N}\right)}}{N}}{N}}{-N} \]
      10. add-sqr-sqrt99.8%

        \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\frac{-\left(0.1111111111111111 + \left(-\frac{--0.25}{\color{blue}{N}}\right) \cdot \frac{-0.25}{N}\right)}{-\left(0.3333333333333333 - \frac{-0.25}{N}\right)}}{N}}{N}}{-N} \]
      11. distribute-frac-neg299.8%

        \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\frac{-\left(0.1111111111111111 + \color{blue}{\frac{--0.25}{-N}} \cdot \frac{-0.25}{N}\right)}{-\left(0.3333333333333333 - \frac{-0.25}{N}\right)}}{N}}{N}}{-N} \]
      12. frac-2neg99.8%

        \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\frac{-\left(0.1111111111111111 + \color{blue}{\frac{-0.25}{N}} \cdot \frac{-0.25}{N}\right)}{-\left(0.3333333333333333 - \frac{-0.25}{N}\right)}}{N}}{N}}{-N} \]
      13. frac-times99.8%

        \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\frac{-\left(0.1111111111111111 + \color{blue}{\frac{-0.25 \cdot -0.25}{N \cdot N}}\right)}{-\left(0.3333333333333333 - \frac{-0.25}{N}\right)}}{N}}{N}}{-N} \]
      14. metadata-eval99.8%

        \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\frac{-\left(0.1111111111111111 + \frac{\color{blue}{0.0625}}{N \cdot N}\right)}{-\left(0.3333333333333333 - \frac{-0.25}{N}\right)}}{N}}{N}}{-N} \]
      15. pow299.8%

        \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\frac{-\left(0.1111111111111111 + \frac{0.0625}{\color{blue}{{N}^{2}}}\right)}{-\left(0.3333333333333333 - \frac{-0.25}{N}\right)}}{N}}{N}}{-N} \]
      16. sub-neg99.8%

        \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\frac{-\left(0.1111111111111111 + \frac{0.0625}{{N}^{2}}\right)}{-\color{blue}{\left(0.3333333333333333 + \left(-\frac{-0.25}{N}\right)\right)}}}{N}}{N}}{-N} \]
      17. frac-2neg99.8%

        \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\frac{-\left(0.1111111111111111 + \frac{0.0625}{{N}^{2}}\right)}{-\left(0.3333333333333333 + \left(-\color{blue}{\frac{--0.25}{-N}}\right)\right)}}{N}}{N}}{-N} \]
    9. Applied egg-rr99.8%

      \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\color{blue}{\frac{-\left(0.1111111111111111 + \frac{0.0625}{{N}^{2}}\right)}{\frac{-0.25}{N} + -0.3333333333333333}}}{N}}{N}}{-N} \]
    10. Step-by-step derivation
      1. distribute-frac-neg99.8%

        \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\color{blue}{-\frac{0.1111111111111111 + \frac{0.0625}{{N}^{2}}}{\frac{-0.25}{N} + -0.3333333333333333}}}{N}}{N}}{-N} \]
      2. distribute-neg-frac299.8%

        \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\color{blue}{\frac{0.1111111111111111 + \frac{0.0625}{{N}^{2}}}{-\left(\frac{-0.25}{N} + -0.3333333333333333\right)}}}{N}}{N}}{-N} \]
      3. neg-mul-199.8%

        \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\frac{0.1111111111111111 + \frac{0.0625}{{N}^{2}}}{\color{blue}{-1 \cdot \left(\frac{-0.25}{N} + -0.3333333333333333\right)}}}{N}}{N}}{-N} \]
      4. +-commutative99.8%

        \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\frac{0.1111111111111111 + \frac{0.0625}{{N}^{2}}}{-1 \cdot \color{blue}{\left(-0.3333333333333333 + \frac{-0.25}{N}\right)}}}{N}}{N}}{-N} \]
      5. distribute-lft-in99.8%

        \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\frac{0.1111111111111111 + \frac{0.0625}{{N}^{2}}}{\color{blue}{-1 \cdot -0.3333333333333333 + -1 \cdot \frac{-0.25}{N}}}}{N}}{N}}{-N} \]
      6. metadata-eval99.8%

        \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\frac{0.1111111111111111 + \frac{0.0625}{{N}^{2}}}{\color{blue}{0.3333333333333333} + -1 \cdot \frac{-0.25}{N}}}{N}}{N}}{-N} \]
      7. associate-*r/99.8%

        \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\frac{0.1111111111111111 + \frac{0.0625}{{N}^{2}}}{0.3333333333333333 + \color{blue}{\frac{-1 \cdot -0.25}{N}}}}{N}}{N}}{-N} \]
      8. metadata-eval99.8%

        \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\frac{0.1111111111111111 + \frac{0.0625}{{N}^{2}}}{0.3333333333333333 + \frac{\color{blue}{0.25}}{N}}}{N}}{N}}{-N} \]
    11. Simplified99.8%

      \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\color{blue}{\frac{0.1111111111111111 + \frac{0.0625}{{N}^{2}}}{0.3333333333333333 + \frac{0.25}{N}}}}{N}}{N}}{-N} \]
    12. Taylor expanded in N around -inf 99.8%

      \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\color{blue}{0.3333333333333333 + -1 \cdot \frac{0.25 - 0.375 \cdot \frac{1}{N}}{N}}}{N}}{N}}{-N} \]
    13. Step-by-step derivation
      1. mul-1-neg99.8%

        \[\leadsto \frac{-1 - \frac{-0.5 + \frac{0.3333333333333333 + \color{blue}{\left(-\frac{0.25 - 0.375 \cdot \frac{1}{N}}{N}\right)}}{N}}{N}}{-N} \]
      2. unsub-neg99.8%

        \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\color{blue}{0.3333333333333333 - \frac{0.25 - 0.375 \cdot \frac{1}{N}}{N}}}{N}}{N}}{-N} \]
      3. sub-neg99.8%

        \[\leadsto \frac{-1 - \frac{-0.5 + \frac{0.3333333333333333 - \frac{\color{blue}{0.25 + \left(-0.375 \cdot \frac{1}{N}\right)}}{N}}{N}}{N}}{-N} \]
      4. associate-*r/99.8%

        \[\leadsto \frac{-1 - \frac{-0.5 + \frac{0.3333333333333333 - \frac{0.25 + \left(-\color{blue}{\frac{0.375 \cdot 1}{N}}\right)}{N}}{N}}{N}}{-N} \]
      5. metadata-eval99.8%

        \[\leadsto \frac{-1 - \frac{-0.5 + \frac{0.3333333333333333 - \frac{0.25 + \left(-\frac{\color{blue}{0.375}}{N}\right)}{N}}{N}}{N}}{-N} \]
      6. distribute-neg-frac99.8%

        \[\leadsto \frac{-1 - \frac{-0.5 + \frac{0.3333333333333333 - \frac{0.25 + \color{blue}{\frac{-0.375}{N}}}{N}}{N}}{N}}{-N} \]
      7. metadata-eval99.8%

        \[\leadsto \frac{-1 - \frac{-0.5 + \frac{0.3333333333333333 - \frac{0.25 + \frac{\color{blue}{-0.375}}{N}}{N}}{N}}{N}}{-N} \]
    14. Simplified99.8%

      \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\color{blue}{0.3333333333333333 - \frac{0.25 + \frac{-0.375}{N}}{N}}}{N}}{N}}{-N} \]

    if 5.99999999999999947e-4 < (-.f64 (log.f64 (+.f64 N #s(literal 1 binary64))) (log.f64 N))

    1. Initial program 90.0%

      \[\log \left(N + 1\right) - \log N \]
    2. Step-by-step derivation
      1. +-commutative90.0%

        \[\leadsto \log \color{blue}{\left(1 + N\right)} - \log N \]
      2. log1p-define90.2%

        \[\leadsto \color{blue}{\mathsf{log1p}\left(N\right)} - \log N \]
    3. Simplified90.2%

      \[\leadsto \color{blue}{\mathsf{log1p}\left(N\right) - \log N} \]
    4. Add Preprocessing
    5. Step-by-step derivation
      1. add-cube-cbrt90.4%

        \[\leadsto \color{blue}{\left(\sqrt[3]{\mathsf{log1p}\left(N\right) - \log N} \cdot \sqrt[3]{\mathsf{log1p}\left(N\right) - \log N}\right) \cdot \sqrt[3]{\mathsf{log1p}\left(N\right) - \log N}} \]
      2. pow390.3%

        \[\leadsto \color{blue}{{\left(\sqrt[3]{\mathsf{log1p}\left(N\right) - \log N}\right)}^{3}} \]
      3. pow-to-exp90.4%

        \[\leadsto \color{blue}{e^{\log \left(\sqrt[3]{\mathsf{log1p}\left(N\right) - \log N}\right) \cdot 3}} \]
    6. Applied egg-rr90.4%

      \[\leadsto \color{blue}{e^{\log \left(\sqrt[3]{\mathsf{log1p}\left(N\right) - \log N}\right) \cdot 3}} \]
    7. Step-by-step derivation
      1. exp-to-pow90.3%

        \[\leadsto \color{blue}{{\left(\sqrt[3]{\mathsf{log1p}\left(N\right) - \log N}\right)}^{3}} \]
      2. rem-cube-cbrt90.2%

        \[\leadsto \color{blue}{\mathsf{log1p}\left(N\right) - \log N} \]
      3. log1p-undefine90.0%

        \[\leadsto \color{blue}{\log \left(1 + N\right)} - \log N \]
      4. +-commutative90.0%

        \[\leadsto \log \color{blue}{\left(N + 1\right)} - \log N \]
      5. diff-log93.6%

        \[\leadsto \color{blue}{\log \left(\frac{N + 1}{N}\right)} \]
      6. clear-num93.5%

        \[\leadsto \log \color{blue}{\left(\frac{1}{\frac{N}{N + 1}}\right)} \]
      7. log-div93.9%

        \[\leadsto \color{blue}{\log 1 - \log \left(\frac{N}{N + 1}\right)} \]
      8. metadata-eval93.9%

        \[\leadsto \color{blue}{0} - \log \left(\frac{N}{N + 1}\right) \]
    8. Applied egg-rr93.9%

      \[\leadsto \color{blue}{0 - \log \left(\frac{N}{N + 1}\right)} \]
    9. Step-by-step derivation
      1. neg-sub093.9%

        \[\leadsto \color{blue}{-\log \left(\frac{N}{N + 1}\right)} \]
    10. Simplified93.9%

      \[\leadsto \color{blue}{-\log \left(\frac{N}{N + 1}\right)} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification99.2%

    \[\leadsto \begin{array}{l} \mathbf{if}\;\log \left(N + 1\right) - \log N \leq 0.0006:\\ \;\;\;\;\frac{1 - \frac{\frac{\frac{0.25 + \frac{-0.375}{N}}{N} - 0.3333333333333333}{N} - -0.5}{N}}{N}\\ \mathbf{else}:\\ \;\;\;\;-\log \left(\frac{N}{N + 1}\right)\\ \end{array} \]
  5. Add Preprocessing

Alternative 2: 99.3% accurate, 1.9× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;N \leq 1450:\\ \;\;\;\;\log \left(\frac{N + 1}{N}\right)\\ \mathbf{else}:\\ \;\;\;\;\frac{1 - \frac{\frac{\frac{0.25 + \frac{-0.375}{N}}{N} - 0.3333333333333333}{N} - -0.5}{N}}{N}\\ \end{array} \end{array} \]
(FPCore (N)
 :precision binary64
 (if (<= N 1450.0)
   (log (/ (+ N 1.0) N))
   (/
    (-
     1.0
     (/ (- (/ (- (/ (+ 0.25 (/ -0.375 N)) N) 0.3333333333333333) N) -0.5) N))
    N)))
double code(double N) {
	double tmp;
	if (N <= 1450.0) {
		tmp = log(((N + 1.0) / N));
	} else {
		tmp = (1.0 - ((((((0.25 + (-0.375 / N)) / N) - 0.3333333333333333) / N) - -0.5) / N)) / N;
	}
	return tmp;
}
real(8) function code(n)
    real(8), intent (in) :: n
    real(8) :: tmp
    if (n <= 1450.0d0) then
        tmp = log(((n + 1.0d0) / n))
    else
        tmp = (1.0d0 - ((((((0.25d0 + ((-0.375d0) / n)) / n) - 0.3333333333333333d0) / n) - (-0.5d0)) / n)) / n
    end if
    code = tmp
end function
public static double code(double N) {
	double tmp;
	if (N <= 1450.0) {
		tmp = Math.log(((N + 1.0) / N));
	} else {
		tmp = (1.0 - ((((((0.25 + (-0.375 / N)) / N) - 0.3333333333333333) / N) - -0.5) / N)) / N;
	}
	return tmp;
}
def code(N):
	tmp = 0
	if N <= 1450.0:
		tmp = math.log(((N + 1.0) / N))
	else:
		tmp = (1.0 - ((((((0.25 + (-0.375 / N)) / N) - 0.3333333333333333) / N) - -0.5) / N)) / N
	return tmp
function code(N)
	tmp = 0.0
	if (N <= 1450.0)
		tmp = log(Float64(Float64(N + 1.0) / N));
	else
		tmp = Float64(Float64(1.0 - Float64(Float64(Float64(Float64(Float64(Float64(0.25 + Float64(-0.375 / N)) / N) - 0.3333333333333333) / N) - -0.5) / N)) / N);
	end
	return tmp
end
function tmp_2 = code(N)
	tmp = 0.0;
	if (N <= 1450.0)
		tmp = log(((N + 1.0) / N));
	else
		tmp = (1.0 - ((((((0.25 + (-0.375 / N)) / N) - 0.3333333333333333) / N) - -0.5) / N)) / N;
	end
	tmp_2 = tmp;
end
code[N_] := If[LessEqual[N, 1450.0], N[Log[N[(N[(N + 1.0), $MachinePrecision] / N), $MachinePrecision]], $MachinePrecision], N[(N[(1.0 - N[(N[(N[(N[(N[(N[(0.25 + N[(-0.375 / N), $MachinePrecision]), $MachinePrecision] / N), $MachinePrecision] - 0.3333333333333333), $MachinePrecision] / N), $MachinePrecision] - -0.5), $MachinePrecision] / N), $MachinePrecision]), $MachinePrecision] / N), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;N \leq 1450:\\
\;\;\;\;\log \left(\frac{N + 1}{N}\right)\\

\mathbf{else}:\\
\;\;\;\;\frac{1 - \frac{\frac{\frac{0.25 + \frac{-0.375}{N}}{N} - 0.3333333333333333}{N} - -0.5}{N}}{N}\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if N < 1450

    1. Initial program 90.0%

      \[\log \left(N + 1\right) - \log N \]
    2. Step-by-step derivation
      1. +-commutative90.0%

        \[\leadsto \log \color{blue}{\left(1 + N\right)} - \log N \]
      2. log1p-define90.2%

        \[\leadsto \color{blue}{\mathsf{log1p}\left(N\right)} - \log N \]
    3. Simplified90.2%

      \[\leadsto \color{blue}{\mathsf{log1p}\left(N\right) - \log N} \]
    4. Add Preprocessing
    5. Step-by-step derivation
      1. add-log-exp90.2%

        \[\leadsto \color{blue}{\log \left(e^{\mathsf{log1p}\left(N\right)}\right)} - \log N \]
      2. log1p-expm1-u90.0%

        \[\leadsto \log \left(e^{\mathsf{log1p}\left(N\right)}\right) - \color{blue}{\mathsf{log1p}\left(\mathsf{expm1}\left(\log N\right)\right)} \]
      3. log1p-undefine90.2%

        \[\leadsto \log \left(e^{\mathsf{log1p}\left(N\right)}\right) - \color{blue}{\log \left(1 + \mathsf{expm1}\left(\log N\right)\right)} \]
      4. diff-log89.9%

        \[\leadsto \color{blue}{\log \left(\frac{e^{\mathsf{log1p}\left(N\right)}}{1 + \mathsf{expm1}\left(\log N\right)}\right)} \]
      5. log1p-undefine89.6%

        \[\leadsto \log \left(\frac{e^{\color{blue}{\log \left(1 + N\right)}}}{1 + \mathsf{expm1}\left(\log N\right)}\right) \]
      6. rem-exp-log90.6%

        \[\leadsto \log \left(\frac{\color{blue}{1 + N}}{1 + \mathsf{expm1}\left(\log N\right)}\right) \]
      7. +-commutative90.6%

        \[\leadsto \log \left(\frac{\color{blue}{N + 1}}{1 + \mathsf{expm1}\left(\log N\right)}\right) \]
      8. add-exp-log90.8%

        \[\leadsto \log \left(\frac{N + 1}{\color{blue}{e^{\log \left(1 + \mathsf{expm1}\left(\log N\right)\right)}}}\right) \]
      9. log1p-undefine90.5%

        \[\leadsto \log \left(\frac{N + 1}{e^{\color{blue}{\mathsf{log1p}\left(\mathsf{expm1}\left(\log N\right)\right)}}}\right) \]
      10. log1p-expm1-u90.8%

        \[\leadsto \log \left(\frac{N + 1}{e^{\color{blue}{\log N}}}\right) \]
      11. add-exp-log93.6%

        \[\leadsto \log \left(\frac{N + 1}{\color{blue}{N}}\right) \]
    6. Applied egg-rr93.6%

      \[\leadsto \color{blue}{\log \left(\frac{N + 1}{N}\right)} \]

    if 1450 < N

    1. Initial program 16.5%

      \[\log \left(N + 1\right) - \log N \]
    2. Step-by-step derivation
      1. +-commutative16.5%

        \[\leadsto \log \color{blue}{\left(1 + N\right)} - \log N \]
      2. log1p-define16.5%

        \[\leadsto \color{blue}{\mathsf{log1p}\left(N\right)} - \log N \]
    3. Simplified16.5%

      \[\leadsto \color{blue}{\mathsf{log1p}\left(N\right) - \log N} \]
    4. Add Preprocessing
    5. Taylor expanded in N around -inf 99.8%

      \[\leadsto \color{blue}{-1 \cdot \frac{-1 \cdot \frac{-1 \cdot \frac{0.25 \cdot \frac{1}{N} - 0.3333333333333333}{N} - 0.5}{N} - 1}{N}} \]
    6. Step-by-step derivation
      1. mul-1-neg99.8%

        \[\leadsto \color{blue}{-\frac{-1 \cdot \frac{-1 \cdot \frac{0.25 \cdot \frac{1}{N} - 0.3333333333333333}{N} - 0.5}{N} - 1}{N}} \]
      2. distribute-neg-frac299.8%

        \[\leadsto \color{blue}{\frac{-1 \cdot \frac{-1 \cdot \frac{0.25 \cdot \frac{1}{N} - 0.3333333333333333}{N} - 0.5}{N} - 1}{-N}} \]
    7. Simplified99.8%

      \[\leadsto \color{blue}{\frac{-1 - \frac{-0.5 + \frac{0.3333333333333333 + \frac{-0.25}{N}}{N}}{N}}{-N}} \]
    8. Step-by-step derivation
      1. flip-+99.8%

        \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\color{blue}{\frac{0.3333333333333333 \cdot 0.3333333333333333 - \frac{-0.25}{N} \cdot \frac{-0.25}{N}}{0.3333333333333333 - \frac{-0.25}{N}}}}{N}}{N}}{-N} \]
      2. frac-2neg99.8%

        \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\color{blue}{\frac{-\left(0.3333333333333333 \cdot 0.3333333333333333 - \frac{-0.25}{N} \cdot \frac{-0.25}{N}\right)}{-\left(0.3333333333333333 - \frac{-0.25}{N}\right)}}}{N}}{N}}{-N} \]
      3. cancel-sign-sub-inv99.8%

        \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\frac{-\color{blue}{\left(0.3333333333333333 \cdot 0.3333333333333333 + \left(-\frac{-0.25}{N}\right) \cdot \frac{-0.25}{N}\right)}}{-\left(0.3333333333333333 - \frac{-0.25}{N}\right)}}{N}}{N}}{-N} \]
      4. metadata-eval99.8%

        \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\frac{-\left(\color{blue}{0.1111111111111111} + \left(-\frac{-0.25}{N}\right) \cdot \frac{-0.25}{N}\right)}{-\left(0.3333333333333333 - \frac{-0.25}{N}\right)}}{N}}{N}}{-N} \]
      5. frac-2neg99.8%

        \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\frac{-\left(0.1111111111111111 + \left(-\color{blue}{\frac{--0.25}{-N}}\right) \cdot \frac{-0.25}{N}\right)}{-\left(0.3333333333333333 - \frac{-0.25}{N}\right)}}{N}}{N}}{-N} \]
      6. add-sqr-sqrt0.0%

        \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\frac{-\left(0.1111111111111111 + \left(-\frac{--0.25}{\color{blue}{\sqrt{-N} \cdot \sqrt{-N}}}\right) \cdot \frac{-0.25}{N}\right)}{-\left(0.3333333333333333 - \frac{-0.25}{N}\right)}}{N}}{N}}{-N} \]
      7. sqrt-unprod99.8%

        \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\frac{-\left(0.1111111111111111 + \left(-\frac{--0.25}{\color{blue}{\sqrt{\left(-N\right) \cdot \left(-N\right)}}}\right) \cdot \frac{-0.25}{N}\right)}{-\left(0.3333333333333333 - \frac{-0.25}{N}\right)}}{N}}{N}}{-N} \]
      8. sqr-neg99.8%

        \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\frac{-\left(0.1111111111111111 + \left(-\frac{--0.25}{\sqrt{\color{blue}{N \cdot N}}}\right) \cdot \frac{-0.25}{N}\right)}{-\left(0.3333333333333333 - \frac{-0.25}{N}\right)}}{N}}{N}}{-N} \]
      9. sqrt-unprod99.8%

        \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\frac{-\left(0.1111111111111111 + \left(-\frac{--0.25}{\color{blue}{\sqrt{N} \cdot \sqrt{N}}}\right) \cdot \frac{-0.25}{N}\right)}{-\left(0.3333333333333333 - \frac{-0.25}{N}\right)}}{N}}{N}}{-N} \]
      10. add-sqr-sqrt99.8%

        \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\frac{-\left(0.1111111111111111 + \left(-\frac{--0.25}{\color{blue}{N}}\right) \cdot \frac{-0.25}{N}\right)}{-\left(0.3333333333333333 - \frac{-0.25}{N}\right)}}{N}}{N}}{-N} \]
      11. distribute-frac-neg299.8%

        \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\frac{-\left(0.1111111111111111 + \color{blue}{\frac{--0.25}{-N}} \cdot \frac{-0.25}{N}\right)}{-\left(0.3333333333333333 - \frac{-0.25}{N}\right)}}{N}}{N}}{-N} \]
      12. frac-2neg99.8%

        \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\frac{-\left(0.1111111111111111 + \color{blue}{\frac{-0.25}{N}} \cdot \frac{-0.25}{N}\right)}{-\left(0.3333333333333333 - \frac{-0.25}{N}\right)}}{N}}{N}}{-N} \]
      13. frac-times99.8%

        \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\frac{-\left(0.1111111111111111 + \color{blue}{\frac{-0.25 \cdot -0.25}{N \cdot N}}\right)}{-\left(0.3333333333333333 - \frac{-0.25}{N}\right)}}{N}}{N}}{-N} \]
      14. metadata-eval99.8%

        \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\frac{-\left(0.1111111111111111 + \frac{\color{blue}{0.0625}}{N \cdot N}\right)}{-\left(0.3333333333333333 - \frac{-0.25}{N}\right)}}{N}}{N}}{-N} \]
      15. pow299.8%

        \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\frac{-\left(0.1111111111111111 + \frac{0.0625}{\color{blue}{{N}^{2}}}\right)}{-\left(0.3333333333333333 - \frac{-0.25}{N}\right)}}{N}}{N}}{-N} \]
      16. sub-neg99.8%

        \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\frac{-\left(0.1111111111111111 + \frac{0.0625}{{N}^{2}}\right)}{-\color{blue}{\left(0.3333333333333333 + \left(-\frac{-0.25}{N}\right)\right)}}}{N}}{N}}{-N} \]
      17. frac-2neg99.8%

        \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\frac{-\left(0.1111111111111111 + \frac{0.0625}{{N}^{2}}\right)}{-\left(0.3333333333333333 + \left(-\color{blue}{\frac{--0.25}{-N}}\right)\right)}}{N}}{N}}{-N} \]
    9. Applied egg-rr99.8%

      \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\color{blue}{\frac{-\left(0.1111111111111111 + \frac{0.0625}{{N}^{2}}\right)}{\frac{-0.25}{N} + -0.3333333333333333}}}{N}}{N}}{-N} \]
    10. Step-by-step derivation
      1. distribute-frac-neg99.8%

        \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\color{blue}{-\frac{0.1111111111111111 + \frac{0.0625}{{N}^{2}}}{\frac{-0.25}{N} + -0.3333333333333333}}}{N}}{N}}{-N} \]
      2. distribute-neg-frac299.8%

        \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\color{blue}{\frac{0.1111111111111111 + \frac{0.0625}{{N}^{2}}}{-\left(\frac{-0.25}{N} + -0.3333333333333333\right)}}}{N}}{N}}{-N} \]
      3. neg-mul-199.8%

        \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\frac{0.1111111111111111 + \frac{0.0625}{{N}^{2}}}{\color{blue}{-1 \cdot \left(\frac{-0.25}{N} + -0.3333333333333333\right)}}}{N}}{N}}{-N} \]
      4. +-commutative99.8%

        \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\frac{0.1111111111111111 + \frac{0.0625}{{N}^{2}}}{-1 \cdot \color{blue}{\left(-0.3333333333333333 + \frac{-0.25}{N}\right)}}}{N}}{N}}{-N} \]
      5. distribute-lft-in99.8%

        \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\frac{0.1111111111111111 + \frac{0.0625}{{N}^{2}}}{\color{blue}{-1 \cdot -0.3333333333333333 + -1 \cdot \frac{-0.25}{N}}}}{N}}{N}}{-N} \]
      6. metadata-eval99.8%

        \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\frac{0.1111111111111111 + \frac{0.0625}{{N}^{2}}}{\color{blue}{0.3333333333333333} + -1 \cdot \frac{-0.25}{N}}}{N}}{N}}{-N} \]
      7. associate-*r/99.8%

        \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\frac{0.1111111111111111 + \frac{0.0625}{{N}^{2}}}{0.3333333333333333 + \color{blue}{\frac{-1 \cdot -0.25}{N}}}}{N}}{N}}{-N} \]
      8. metadata-eval99.8%

        \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\frac{0.1111111111111111 + \frac{0.0625}{{N}^{2}}}{0.3333333333333333 + \frac{\color{blue}{0.25}}{N}}}{N}}{N}}{-N} \]
    11. Simplified99.8%

      \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\color{blue}{\frac{0.1111111111111111 + \frac{0.0625}{{N}^{2}}}{0.3333333333333333 + \frac{0.25}{N}}}}{N}}{N}}{-N} \]
    12. Taylor expanded in N around -inf 99.8%

      \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\color{blue}{0.3333333333333333 + -1 \cdot \frac{0.25 - 0.375 \cdot \frac{1}{N}}{N}}}{N}}{N}}{-N} \]
    13. Step-by-step derivation
      1. mul-1-neg99.8%

        \[\leadsto \frac{-1 - \frac{-0.5 + \frac{0.3333333333333333 + \color{blue}{\left(-\frac{0.25 - 0.375 \cdot \frac{1}{N}}{N}\right)}}{N}}{N}}{-N} \]
      2. unsub-neg99.8%

        \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\color{blue}{0.3333333333333333 - \frac{0.25 - 0.375 \cdot \frac{1}{N}}{N}}}{N}}{N}}{-N} \]
      3. sub-neg99.8%

        \[\leadsto \frac{-1 - \frac{-0.5 + \frac{0.3333333333333333 - \frac{\color{blue}{0.25 + \left(-0.375 \cdot \frac{1}{N}\right)}}{N}}{N}}{N}}{-N} \]
      4. associate-*r/99.8%

        \[\leadsto \frac{-1 - \frac{-0.5 + \frac{0.3333333333333333 - \frac{0.25 + \left(-\color{blue}{\frac{0.375 \cdot 1}{N}}\right)}{N}}{N}}{N}}{-N} \]
      5. metadata-eval99.8%

        \[\leadsto \frac{-1 - \frac{-0.5 + \frac{0.3333333333333333 - \frac{0.25 + \left(-\frac{\color{blue}{0.375}}{N}\right)}{N}}{N}}{N}}{-N} \]
      6. distribute-neg-frac99.8%

        \[\leadsto \frac{-1 - \frac{-0.5 + \frac{0.3333333333333333 - \frac{0.25 + \color{blue}{\frac{-0.375}{N}}}{N}}{N}}{N}}{-N} \]
      7. metadata-eval99.8%

        \[\leadsto \frac{-1 - \frac{-0.5 + \frac{0.3333333333333333 - \frac{0.25 + \frac{\color{blue}{-0.375}}{N}}{N}}{N}}{N}}{-N} \]
    14. Simplified99.8%

      \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\color{blue}{0.3333333333333333 - \frac{0.25 + \frac{-0.375}{N}}{N}}}{N}}{N}}{-N} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification99.2%

    \[\leadsto \begin{array}{l} \mathbf{if}\;N \leq 1450:\\ \;\;\;\;\log \left(\frac{N + 1}{N}\right)\\ \mathbf{else}:\\ \;\;\;\;\frac{1 - \frac{\frac{\frac{0.25 + \frac{-0.375}{N}}{N} - 0.3333333333333333}{N} - -0.5}{N}}{N}\\ \end{array} \]
  5. Add Preprocessing

Alternative 3: 96.2% accurate, 8.9× speedup?

\[\begin{array}{l} \\ \frac{\frac{-0.5 + \frac{0.3333333333333333 + \frac{-0.25 + \frac{0.375 + \frac{-0.28125}{N}}{N}}{N}}{N}}{N} + 1}{N} \end{array} \]
(FPCore (N)
 :precision binary64
 (/
  (+
   (/
    (+
     -0.5
     (/
      (+ 0.3333333333333333 (/ (+ -0.25 (/ (+ 0.375 (/ -0.28125 N)) N)) N))
      N))
    N)
   1.0)
  N))
double code(double N) {
	return (((-0.5 + ((0.3333333333333333 + ((-0.25 + ((0.375 + (-0.28125 / N)) / N)) / N)) / N)) / N) + 1.0) / N;
}
real(8) function code(n)
    real(8), intent (in) :: n
    code = ((((-0.5d0) + ((0.3333333333333333d0 + (((-0.25d0) + ((0.375d0 + ((-0.28125d0) / n)) / n)) / n)) / n)) / n) + 1.0d0) / n
end function
public static double code(double N) {
	return (((-0.5 + ((0.3333333333333333 + ((-0.25 + ((0.375 + (-0.28125 / N)) / N)) / N)) / N)) / N) + 1.0) / N;
}
def code(N):
	return (((-0.5 + ((0.3333333333333333 + ((-0.25 + ((0.375 + (-0.28125 / N)) / N)) / N)) / N)) / N) + 1.0) / N
function code(N)
	return Float64(Float64(Float64(Float64(-0.5 + Float64(Float64(0.3333333333333333 + Float64(Float64(-0.25 + Float64(Float64(0.375 + Float64(-0.28125 / N)) / N)) / N)) / N)) / N) + 1.0) / N)
end
function tmp = code(N)
	tmp = (((-0.5 + ((0.3333333333333333 + ((-0.25 + ((0.375 + (-0.28125 / N)) / N)) / N)) / N)) / N) + 1.0) / N;
end
code[N_] := N[(N[(N[(N[(-0.5 + N[(N[(0.3333333333333333 + N[(N[(-0.25 + N[(N[(0.375 + N[(-0.28125 / N), $MachinePrecision]), $MachinePrecision] / N), $MachinePrecision]), $MachinePrecision] / N), $MachinePrecision]), $MachinePrecision] / N), $MachinePrecision]), $MachinePrecision] / N), $MachinePrecision] + 1.0), $MachinePrecision] / N), $MachinePrecision]
\begin{array}{l}

\\
\frac{\frac{-0.5 + \frac{0.3333333333333333 + \frac{-0.25 + \frac{0.375 + \frac{-0.28125}{N}}{N}}{N}}{N}}{N} + 1}{N}
\end{array}
Derivation
  1. Initial program 23.4%

    \[\log \left(N + 1\right) - \log N \]
  2. Step-by-step derivation
    1. +-commutative23.4%

      \[\leadsto \log \color{blue}{\left(1 + N\right)} - \log N \]
    2. log1p-define23.4%

      \[\leadsto \color{blue}{\mathsf{log1p}\left(N\right)} - \log N \]
  3. Simplified23.4%

    \[\leadsto \color{blue}{\mathsf{log1p}\left(N\right) - \log N} \]
  4. Add Preprocessing
  5. Taylor expanded in N around -inf 96.1%

    \[\leadsto \color{blue}{-1 \cdot \frac{-1 \cdot \frac{-1 \cdot \frac{0.25 \cdot \frac{1}{N} - 0.3333333333333333}{N} - 0.5}{N} - 1}{N}} \]
  6. Step-by-step derivation
    1. mul-1-neg96.1%

      \[\leadsto \color{blue}{-\frac{-1 \cdot \frac{-1 \cdot \frac{0.25 \cdot \frac{1}{N} - 0.3333333333333333}{N} - 0.5}{N} - 1}{N}} \]
    2. distribute-neg-frac296.1%

      \[\leadsto \color{blue}{\frac{-1 \cdot \frac{-1 \cdot \frac{0.25 \cdot \frac{1}{N} - 0.3333333333333333}{N} - 0.5}{N} - 1}{-N}} \]
  7. Simplified96.1%

    \[\leadsto \color{blue}{\frac{-1 - \frac{-0.5 + \frac{0.3333333333333333 + \frac{-0.25}{N}}{N}}{N}}{-N}} \]
  8. Step-by-step derivation
    1. flip-+96.1%

      \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\color{blue}{\frac{0.3333333333333333 \cdot 0.3333333333333333 - \frac{-0.25}{N} \cdot \frac{-0.25}{N}}{0.3333333333333333 - \frac{-0.25}{N}}}}{N}}{N}}{-N} \]
    2. frac-2neg96.1%

      \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\color{blue}{\frac{-\left(0.3333333333333333 \cdot 0.3333333333333333 - \frac{-0.25}{N} \cdot \frac{-0.25}{N}\right)}{-\left(0.3333333333333333 - \frac{-0.25}{N}\right)}}}{N}}{N}}{-N} \]
    3. cancel-sign-sub-inv96.1%

      \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\frac{-\color{blue}{\left(0.3333333333333333 \cdot 0.3333333333333333 + \left(-\frac{-0.25}{N}\right) \cdot \frac{-0.25}{N}\right)}}{-\left(0.3333333333333333 - \frac{-0.25}{N}\right)}}{N}}{N}}{-N} \]
    4. metadata-eval96.1%

      \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\frac{-\left(\color{blue}{0.1111111111111111} + \left(-\frac{-0.25}{N}\right) \cdot \frac{-0.25}{N}\right)}{-\left(0.3333333333333333 - \frac{-0.25}{N}\right)}}{N}}{N}}{-N} \]
    5. frac-2neg96.1%

      \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\frac{-\left(0.1111111111111111 + \left(-\color{blue}{\frac{--0.25}{-N}}\right) \cdot \frac{-0.25}{N}\right)}{-\left(0.3333333333333333 - \frac{-0.25}{N}\right)}}{N}}{N}}{-N} \]
    6. add-sqr-sqrt0.0%

      \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\frac{-\left(0.1111111111111111 + \left(-\frac{--0.25}{\color{blue}{\sqrt{-N} \cdot \sqrt{-N}}}\right) \cdot \frac{-0.25}{N}\right)}{-\left(0.3333333333333333 - \frac{-0.25}{N}\right)}}{N}}{N}}{-N} \]
    7. sqrt-unprod96.1%

      \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\frac{-\left(0.1111111111111111 + \left(-\frac{--0.25}{\color{blue}{\sqrt{\left(-N\right) \cdot \left(-N\right)}}}\right) \cdot \frac{-0.25}{N}\right)}{-\left(0.3333333333333333 - \frac{-0.25}{N}\right)}}{N}}{N}}{-N} \]
    8. sqr-neg96.1%

      \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\frac{-\left(0.1111111111111111 + \left(-\frac{--0.25}{\sqrt{\color{blue}{N \cdot N}}}\right) \cdot \frac{-0.25}{N}\right)}{-\left(0.3333333333333333 - \frac{-0.25}{N}\right)}}{N}}{N}}{-N} \]
    9. sqrt-unprod96.1%

      \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\frac{-\left(0.1111111111111111 + \left(-\frac{--0.25}{\color{blue}{\sqrt{N} \cdot \sqrt{N}}}\right) \cdot \frac{-0.25}{N}\right)}{-\left(0.3333333333333333 - \frac{-0.25}{N}\right)}}{N}}{N}}{-N} \]
    10. add-sqr-sqrt96.1%

      \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\frac{-\left(0.1111111111111111 + \left(-\frac{--0.25}{\color{blue}{N}}\right) \cdot \frac{-0.25}{N}\right)}{-\left(0.3333333333333333 - \frac{-0.25}{N}\right)}}{N}}{N}}{-N} \]
    11. distribute-frac-neg296.1%

      \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\frac{-\left(0.1111111111111111 + \color{blue}{\frac{--0.25}{-N}} \cdot \frac{-0.25}{N}\right)}{-\left(0.3333333333333333 - \frac{-0.25}{N}\right)}}{N}}{N}}{-N} \]
    12. frac-2neg96.1%

      \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\frac{-\left(0.1111111111111111 + \color{blue}{\frac{-0.25}{N}} \cdot \frac{-0.25}{N}\right)}{-\left(0.3333333333333333 - \frac{-0.25}{N}\right)}}{N}}{N}}{-N} \]
    13. frac-times96.1%

      \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\frac{-\left(0.1111111111111111 + \color{blue}{\frac{-0.25 \cdot -0.25}{N \cdot N}}\right)}{-\left(0.3333333333333333 - \frac{-0.25}{N}\right)}}{N}}{N}}{-N} \]
    14. metadata-eval96.1%

      \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\frac{-\left(0.1111111111111111 + \frac{\color{blue}{0.0625}}{N \cdot N}\right)}{-\left(0.3333333333333333 - \frac{-0.25}{N}\right)}}{N}}{N}}{-N} \]
    15. pow296.1%

      \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\frac{-\left(0.1111111111111111 + \frac{0.0625}{\color{blue}{{N}^{2}}}\right)}{-\left(0.3333333333333333 - \frac{-0.25}{N}\right)}}{N}}{N}}{-N} \]
    16. sub-neg96.1%

      \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\frac{-\left(0.1111111111111111 + \frac{0.0625}{{N}^{2}}\right)}{-\color{blue}{\left(0.3333333333333333 + \left(-\frac{-0.25}{N}\right)\right)}}}{N}}{N}}{-N} \]
    17. frac-2neg96.1%

      \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\frac{-\left(0.1111111111111111 + \frac{0.0625}{{N}^{2}}\right)}{-\left(0.3333333333333333 + \left(-\color{blue}{\frac{--0.25}{-N}}\right)\right)}}{N}}{N}}{-N} \]
  9. Applied egg-rr96.1%

    \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\color{blue}{\frac{-\left(0.1111111111111111 + \frac{0.0625}{{N}^{2}}\right)}{\frac{-0.25}{N} + -0.3333333333333333}}}{N}}{N}}{-N} \]
  10. Step-by-step derivation
    1. distribute-frac-neg96.1%

      \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\color{blue}{-\frac{0.1111111111111111 + \frac{0.0625}{{N}^{2}}}{\frac{-0.25}{N} + -0.3333333333333333}}}{N}}{N}}{-N} \]
    2. distribute-neg-frac296.1%

      \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\color{blue}{\frac{0.1111111111111111 + \frac{0.0625}{{N}^{2}}}{-\left(\frac{-0.25}{N} + -0.3333333333333333\right)}}}{N}}{N}}{-N} \]
    3. neg-mul-196.1%

      \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\frac{0.1111111111111111 + \frac{0.0625}{{N}^{2}}}{\color{blue}{-1 \cdot \left(\frac{-0.25}{N} + -0.3333333333333333\right)}}}{N}}{N}}{-N} \]
    4. +-commutative96.1%

      \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\frac{0.1111111111111111 + \frac{0.0625}{{N}^{2}}}{-1 \cdot \color{blue}{\left(-0.3333333333333333 + \frac{-0.25}{N}\right)}}}{N}}{N}}{-N} \]
    5. distribute-lft-in96.1%

      \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\frac{0.1111111111111111 + \frac{0.0625}{{N}^{2}}}{\color{blue}{-1 \cdot -0.3333333333333333 + -1 \cdot \frac{-0.25}{N}}}}{N}}{N}}{-N} \]
    6. metadata-eval96.1%

      \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\frac{0.1111111111111111 + \frac{0.0625}{{N}^{2}}}{\color{blue}{0.3333333333333333} + -1 \cdot \frac{-0.25}{N}}}{N}}{N}}{-N} \]
    7. associate-*r/96.1%

      \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\frac{0.1111111111111111 + \frac{0.0625}{{N}^{2}}}{0.3333333333333333 + \color{blue}{\frac{-1 \cdot -0.25}{N}}}}{N}}{N}}{-N} \]
    8. metadata-eval96.1%

      \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\frac{0.1111111111111111 + \frac{0.0625}{{N}^{2}}}{0.3333333333333333 + \frac{\color{blue}{0.25}}{N}}}{N}}{N}}{-N} \]
  11. Simplified96.1%

    \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\color{blue}{\frac{0.1111111111111111 + \frac{0.0625}{{N}^{2}}}{0.3333333333333333 + \frac{0.25}{N}}}}{N}}{N}}{-N} \]
  12. Taylor expanded in N around -inf 96.1%

    \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\color{blue}{0.3333333333333333 + -1 \cdot \frac{0.25 + -1 \cdot \frac{0.375 - 0.28125 \cdot \frac{1}{N}}{N}}{N}}}{N}}{N}}{-N} \]
  13. Step-by-step derivation
    1. mul-1-neg96.1%

      \[\leadsto \frac{-1 - \frac{-0.5 + \frac{0.3333333333333333 + \color{blue}{\left(-\frac{0.25 + -1 \cdot \frac{0.375 - 0.28125 \cdot \frac{1}{N}}{N}}{N}\right)}}{N}}{N}}{-N} \]
    2. unsub-neg96.1%

      \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\color{blue}{0.3333333333333333 - \frac{0.25 + -1 \cdot \frac{0.375 - 0.28125 \cdot \frac{1}{N}}{N}}{N}}}{N}}{N}}{-N} \]
    3. mul-1-neg96.1%

      \[\leadsto \frac{-1 - \frac{-0.5 + \frac{0.3333333333333333 - \frac{0.25 + \color{blue}{\left(-\frac{0.375 - 0.28125 \cdot \frac{1}{N}}{N}\right)}}{N}}{N}}{N}}{-N} \]
    4. unsub-neg96.1%

      \[\leadsto \frac{-1 - \frac{-0.5 + \frac{0.3333333333333333 - \frac{\color{blue}{0.25 - \frac{0.375 - 0.28125 \cdot \frac{1}{N}}{N}}}{N}}{N}}{N}}{-N} \]
    5. associate-*r/96.1%

      \[\leadsto \frac{-1 - \frac{-0.5 + \frac{0.3333333333333333 - \frac{0.25 - \frac{0.375 - \color{blue}{\frac{0.28125 \cdot 1}{N}}}{N}}{N}}{N}}{N}}{-N} \]
    6. metadata-eval96.1%

      \[\leadsto \frac{-1 - \frac{-0.5 + \frac{0.3333333333333333 - \frac{0.25 - \frac{0.375 - \frac{\color{blue}{0.28125}}{N}}{N}}{N}}{N}}{N}}{-N} \]
  14. Simplified96.1%

    \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\color{blue}{0.3333333333333333 - \frac{0.25 - \frac{0.375 - \frac{0.28125}{N}}{N}}{N}}}{N}}{N}}{-N} \]
  15. Step-by-step derivation
    1. div-sub96.1%

      \[\leadsto \color{blue}{\frac{-1}{-N} - \frac{\frac{-0.5 + \frac{0.3333333333333333 - \frac{0.25 - \frac{0.375 - \frac{0.28125}{N}}{N}}{N}}{N}}{N}}{-N}} \]
    2. metadata-eval96.1%

      \[\leadsto \frac{\color{blue}{-1}}{-N} - \frac{\frac{-0.5 + \frac{0.3333333333333333 - \frac{0.25 - \frac{0.375 - \frac{0.28125}{N}}{N}}{N}}{N}}{N}}{-N} \]
    3. frac-2neg96.1%

      \[\leadsto \color{blue}{\frac{1}{N}} - \frac{\frac{-0.5 + \frac{0.3333333333333333 - \frac{0.25 - \frac{0.375 - \frac{0.28125}{N}}{N}}{N}}{N}}{N}}{-N} \]
    4. +-commutative96.1%

      \[\leadsto \frac{1}{N} - \frac{\frac{\color{blue}{\frac{0.3333333333333333 - \frac{0.25 - \frac{0.375 - \frac{0.28125}{N}}{N}}{N}}{N} + -0.5}}{N}}{-N} \]
  16. Applied egg-rr96.1%

    \[\leadsto \color{blue}{\frac{1}{N} - \frac{\frac{\frac{0.3333333333333333 - \frac{0.25 - \frac{0.375 - \frac{0.28125}{N}}{N}}{N}}{N} + -0.5}{N}}{-N}} \]
  17. Simplified96.1%

    \[\leadsto \color{blue}{\frac{1 + \frac{-0.5 + \frac{0.3333333333333333 + \frac{-0.25 + \frac{0.375 + \frac{-0.28125}{N}}{N}}{N}}{N}}{N}}{N}} \]
  18. Final simplification96.1%

    \[\leadsto \frac{\frac{-0.5 + \frac{0.3333333333333333 + \frac{-0.25 + \frac{0.375 + \frac{-0.28125}{N}}{N}}{N}}{N}}{N} + 1}{N} \]
  19. Add Preprocessing

Alternative 4: 96.2% accurate, 10.8× speedup?

\[\begin{array}{l} \\ \frac{1 - \frac{\frac{\frac{0.25 + \frac{-0.375}{N}}{N} - 0.3333333333333333}{N} - -0.5}{N}}{N} \end{array} \]
(FPCore (N)
 :precision binary64
 (/
  (-
   1.0
   (/ (- (/ (- (/ (+ 0.25 (/ -0.375 N)) N) 0.3333333333333333) N) -0.5) N))
  N))
double code(double N) {
	return (1.0 - ((((((0.25 + (-0.375 / N)) / N) - 0.3333333333333333) / N) - -0.5) / N)) / N;
}
real(8) function code(n)
    real(8), intent (in) :: n
    code = (1.0d0 - ((((((0.25d0 + ((-0.375d0) / n)) / n) - 0.3333333333333333d0) / n) - (-0.5d0)) / n)) / n
end function
public static double code(double N) {
	return (1.0 - ((((((0.25 + (-0.375 / N)) / N) - 0.3333333333333333) / N) - -0.5) / N)) / N;
}
def code(N):
	return (1.0 - ((((((0.25 + (-0.375 / N)) / N) - 0.3333333333333333) / N) - -0.5) / N)) / N
function code(N)
	return Float64(Float64(1.0 - Float64(Float64(Float64(Float64(Float64(Float64(0.25 + Float64(-0.375 / N)) / N) - 0.3333333333333333) / N) - -0.5) / N)) / N)
end
function tmp = code(N)
	tmp = (1.0 - ((((((0.25 + (-0.375 / N)) / N) - 0.3333333333333333) / N) - -0.5) / N)) / N;
end
code[N_] := N[(N[(1.0 - N[(N[(N[(N[(N[(N[(0.25 + N[(-0.375 / N), $MachinePrecision]), $MachinePrecision] / N), $MachinePrecision] - 0.3333333333333333), $MachinePrecision] / N), $MachinePrecision] - -0.5), $MachinePrecision] / N), $MachinePrecision]), $MachinePrecision] / N), $MachinePrecision]
\begin{array}{l}

\\
\frac{1 - \frac{\frac{\frac{0.25 + \frac{-0.375}{N}}{N} - 0.3333333333333333}{N} - -0.5}{N}}{N}
\end{array}
Derivation
  1. Initial program 23.4%

    \[\log \left(N + 1\right) - \log N \]
  2. Step-by-step derivation
    1. +-commutative23.4%

      \[\leadsto \log \color{blue}{\left(1 + N\right)} - \log N \]
    2. log1p-define23.4%

      \[\leadsto \color{blue}{\mathsf{log1p}\left(N\right)} - \log N \]
  3. Simplified23.4%

    \[\leadsto \color{blue}{\mathsf{log1p}\left(N\right) - \log N} \]
  4. Add Preprocessing
  5. Taylor expanded in N around -inf 96.1%

    \[\leadsto \color{blue}{-1 \cdot \frac{-1 \cdot \frac{-1 \cdot \frac{0.25 \cdot \frac{1}{N} - 0.3333333333333333}{N} - 0.5}{N} - 1}{N}} \]
  6. Step-by-step derivation
    1. mul-1-neg96.1%

      \[\leadsto \color{blue}{-\frac{-1 \cdot \frac{-1 \cdot \frac{0.25 \cdot \frac{1}{N} - 0.3333333333333333}{N} - 0.5}{N} - 1}{N}} \]
    2. distribute-neg-frac296.1%

      \[\leadsto \color{blue}{\frac{-1 \cdot \frac{-1 \cdot \frac{0.25 \cdot \frac{1}{N} - 0.3333333333333333}{N} - 0.5}{N} - 1}{-N}} \]
  7. Simplified96.1%

    \[\leadsto \color{blue}{\frac{-1 - \frac{-0.5 + \frac{0.3333333333333333 + \frac{-0.25}{N}}{N}}{N}}{-N}} \]
  8. Step-by-step derivation
    1. flip-+96.1%

      \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\color{blue}{\frac{0.3333333333333333 \cdot 0.3333333333333333 - \frac{-0.25}{N} \cdot \frac{-0.25}{N}}{0.3333333333333333 - \frac{-0.25}{N}}}}{N}}{N}}{-N} \]
    2. frac-2neg96.1%

      \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\color{blue}{\frac{-\left(0.3333333333333333 \cdot 0.3333333333333333 - \frac{-0.25}{N} \cdot \frac{-0.25}{N}\right)}{-\left(0.3333333333333333 - \frac{-0.25}{N}\right)}}}{N}}{N}}{-N} \]
    3. cancel-sign-sub-inv96.1%

      \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\frac{-\color{blue}{\left(0.3333333333333333 \cdot 0.3333333333333333 + \left(-\frac{-0.25}{N}\right) \cdot \frac{-0.25}{N}\right)}}{-\left(0.3333333333333333 - \frac{-0.25}{N}\right)}}{N}}{N}}{-N} \]
    4. metadata-eval96.1%

      \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\frac{-\left(\color{blue}{0.1111111111111111} + \left(-\frac{-0.25}{N}\right) \cdot \frac{-0.25}{N}\right)}{-\left(0.3333333333333333 - \frac{-0.25}{N}\right)}}{N}}{N}}{-N} \]
    5. frac-2neg96.1%

      \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\frac{-\left(0.1111111111111111 + \left(-\color{blue}{\frac{--0.25}{-N}}\right) \cdot \frac{-0.25}{N}\right)}{-\left(0.3333333333333333 - \frac{-0.25}{N}\right)}}{N}}{N}}{-N} \]
    6. add-sqr-sqrt0.0%

      \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\frac{-\left(0.1111111111111111 + \left(-\frac{--0.25}{\color{blue}{\sqrt{-N} \cdot \sqrt{-N}}}\right) \cdot \frac{-0.25}{N}\right)}{-\left(0.3333333333333333 - \frac{-0.25}{N}\right)}}{N}}{N}}{-N} \]
    7. sqrt-unprod96.1%

      \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\frac{-\left(0.1111111111111111 + \left(-\frac{--0.25}{\color{blue}{\sqrt{\left(-N\right) \cdot \left(-N\right)}}}\right) \cdot \frac{-0.25}{N}\right)}{-\left(0.3333333333333333 - \frac{-0.25}{N}\right)}}{N}}{N}}{-N} \]
    8. sqr-neg96.1%

      \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\frac{-\left(0.1111111111111111 + \left(-\frac{--0.25}{\sqrt{\color{blue}{N \cdot N}}}\right) \cdot \frac{-0.25}{N}\right)}{-\left(0.3333333333333333 - \frac{-0.25}{N}\right)}}{N}}{N}}{-N} \]
    9. sqrt-unprod96.1%

      \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\frac{-\left(0.1111111111111111 + \left(-\frac{--0.25}{\color{blue}{\sqrt{N} \cdot \sqrt{N}}}\right) \cdot \frac{-0.25}{N}\right)}{-\left(0.3333333333333333 - \frac{-0.25}{N}\right)}}{N}}{N}}{-N} \]
    10. add-sqr-sqrt96.1%

      \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\frac{-\left(0.1111111111111111 + \left(-\frac{--0.25}{\color{blue}{N}}\right) \cdot \frac{-0.25}{N}\right)}{-\left(0.3333333333333333 - \frac{-0.25}{N}\right)}}{N}}{N}}{-N} \]
    11. distribute-frac-neg296.1%

      \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\frac{-\left(0.1111111111111111 + \color{blue}{\frac{--0.25}{-N}} \cdot \frac{-0.25}{N}\right)}{-\left(0.3333333333333333 - \frac{-0.25}{N}\right)}}{N}}{N}}{-N} \]
    12. frac-2neg96.1%

      \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\frac{-\left(0.1111111111111111 + \color{blue}{\frac{-0.25}{N}} \cdot \frac{-0.25}{N}\right)}{-\left(0.3333333333333333 - \frac{-0.25}{N}\right)}}{N}}{N}}{-N} \]
    13. frac-times96.1%

      \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\frac{-\left(0.1111111111111111 + \color{blue}{\frac{-0.25 \cdot -0.25}{N \cdot N}}\right)}{-\left(0.3333333333333333 - \frac{-0.25}{N}\right)}}{N}}{N}}{-N} \]
    14. metadata-eval96.1%

      \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\frac{-\left(0.1111111111111111 + \frac{\color{blue}{0.0625}}{N \cdot N}\right)}{-\left(0.3333333333333333 - \frac{-0.25}{N}\right)}}{N}}{N}}{-N} \]
    15. pow296.1%

      \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\frac{-\left(0.1111111111111111 + \frac{0.0625}{\color{blue}{{N}^{2}}}\right)}{-\left(0.3333333333333333 - \frac{-0.25}{N}\right)}}{N}}{N}}{-N} \]
    16. sub-neg96.1%

      \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\frac{-\left(0.1111111111111111 + \frac{0.0625}{{N}^{2}}\right)}{-\color{blue}{\left(0.3333333333333333 + \left(-\frac{-0.25}{N}\right)\right)}}}{N}}{N}}{-N} \]
    17. frac-2neg96.1%

      \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\frac{-\left(0.1111111111111111 + \frac{0.0625}{{N}^{2}}\right)}{-\left(0.3333333333333333 + \left(-\color{blue}{\frac{--0.25}{-N}}\right)\right)}}{N}}{N}}{-N} \]
  9. Applied egg-rr96.1%

    \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\color{blue}{\frac{-\left(0.1111111111111111 + \frac{0.0625}{{N}^{2}}\right)}{\frac{-0.25}{N} + -0.3333333333333333}}}{N}}{N}}{-N} \]
  10. Step-by-step derivation
    1. distribute-frac-neg96.1%

      \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\color{blue}{-\frac{0.1111111111111111 + \frac{0.0625}{{N}^{2}}}{\frac{-0.25}{N} + -0.3333333333333333}}}{N}}{N}}{-N} \]
    2. distribute-neg-frac296.1%

      \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\color{blue}{\frac{0.1111111111111111 + \frac{0.0625}{{N}^{2}}}{-\left(\frac{-0.25}{N} + -0.3333333333333333\right)}}}{N}}{N}}{-N} \]
    3. neg-mul-196.1%

      \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\frac{0.1111111111111111 + \frac{0.0625}{{N}^{2}}}{\color{blue}{-1 \cdot \left(\frac{-0.25}{N} + -0.3333333333333333\right)}}}{N}}{N}}{-N} \]
    4. +-commutative96.1%

      \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\frac{0.1111111111111111 + \frac{0.0625}{{N}^{2}}}{-1 \cdot \color{blue}{\left(-0.3333333333333333 + \frac{-0.25}{N}\right)}}}{N}}{N}}{-N} \]
    5. distribute-lft-in96.1%

      \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\frac{0.1111111111111111 + \frac{0.0625}{{N}^{2}}}{\color{blue}{-1 \cdot -0.3333333333333333 + -1 \cdot \frac{-0.25}{N}}}}{N}}{N}}{-N} \]
    6. metadata-eval96.1%

      \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\frac{0.1111111111111111 + \frac{0.0625}{{N}^{2}}}{\color{blue}{0.3333333333333333} + -1 \cdot \frac{-0.25}{N}}}{N}}{N}}{-N} \]
    7. associate-*r/96.1%

      \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\frac{0.1111111111111111 + \frac{0.0625}{{N}^{2}}}{0.3333333333333333 + \color{blue}{\frac{-1 \cdot -0.25}{N}}}}{N}}{N}}{-N} \]
    8. metadata-eval96.1%

      \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\frac{0.1111111111111111 + \frac{0.0625}{{N}^{2}}}{0.3333333333333333 + \frac{\color{blue}{0.25}}{N}}}{N}}{N}}{-N} \]
  11. Simplified96.1%

    \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\color{blue}{\frac{0.1111111111111111 + \frac{0.0625}{{N}^{2}}}{0.3333333333333333 + \frac{0.25}{N}}}}{N}}{N}}{-N} \]
  12. Taylor expanded in N around -inf 96.1%

    \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\color{blue}{0.3333333333333333 + -1 \cdot \frac{0.25 - 0.375 \cdot \frac{1}{N}}{N}}}{N}}{N}}{-N} \]
  13. Step-by-step derivation
    1. mul-1-neg96.1%

      \[\leadsto \frac{-1 - \frac{-0.5 + \frac{0.3333333333333333 + \color{blue}{\left(-\frac{0.25 - 0.375 \cdot \frac{1}{N}}{N}\right)}}{N}}{N}}{-N} \]
    2. unsub-neg96.1%

      \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\color{blue}{0.3333333333333333 - \frac{0.25 - 0.375 \cdot \frac{1}{N}}{N}}}{N}}{N}}{-N} \]
    3. sub-neg96.1%

      \[\leadsto \frac{-1 - \frac{-0.5 + \frac{0.3333333333333333 - \frac{\color{blue}{0.25 + \left(-0.375 \cdot \frac{1}{N}\right)}}{N}}{N}}{N}}{-N} \]
    4. associate-*r/96.1%

      \[\leadsto \frac{-1 - \frac{-0.5 + \frac{0.3333333333333333 - \frac{0.25 + \left(-\color{blue}{\frac{0.375 \cdot 1}{N}}\right)}{N}}{N}}{N}}{-N} \]
    5. metadata-eval96.1%

      \[\leadsto \frac{-1 - \frac{-0.5 + \frac{0.3333333333333333 - \frac{0.25 + \left(-\frac{\color{blue}{0.375}}{N}\right)}{N}}{N}}{N}}{-N} \]
    6. distribute-neg-frac96.1%

      \[\leadsto \frac{-1 - \frac{-0.5 + \frac{0.3333333333333333 - \frac{0.25 + \color{blue}{\frac{-0.375}{N}}}{N}}{N}}{N}}{-N} \]
    7. metadata-eval96.1%

      \[\leadsto \frac{-1 - \frac{-0.5 + \frac{0.3333333333333333 - \frac{0.25 + \frac{\color{blue}{-0.375}}{N}}{N}}{N}}{N}}{-N} \]
  14. Simplified96.1%

    \[\leadsto \frac{-1 - \frac{-0.5 + \frac{\color{blue}{0.3333333333333333 - \frac{0.25 + \frac{-0.375}{N}}{N}}}{N}}{N}}{-N} \]
  15. Final simplification96.1%

    \[\leadsto \frac{1 - \frac{\frac{\frac{0.25 + \frac{-0.375}{N}}{N} - 0.3333333333333333}{N} - -0.5}{N}}{N} \]
  16. Add Preprocessing

Alternative 5: 96.2% accurate, 13.7× speedup?

\[\begin{array}{l} \\ \frac{\frac{-0.5 + \frac{0.3333333333333333 + \frac{-0.25}{N}}{N}}{N} + 1}{N} \end{array} \]
(FPCore (N)
 :precision binary64
 (/ (+ (/ (+ -0.5 (/ (+ 0.3333333333333333 (/ -0.25 N)) N)) N) 1.0) N))
double code(double N) {
	return (((-0.5 + ((0.3333333333333333 + (-0.25 / N)) / N)) / N) + 1.0) / N;
}
real(8) function code(n)
    real(8), intent (in) :: n
    code = ((((-0.5d0) + ((0.3333333333333333d0 + ((-0.25d0) / n)) / n)) / n) + 1.0d0) / n
end function
public static double code(double N) {
	return (((-0.5 + ((0.3333333333333333 + (-0.25 / N)) / N)) / N) + 1.0) / N;
}
def code(N):
	return (((-0.5 + ((0.3333333333333333 + (-0.25 / N)) / N)) / N) + 1.0) / N
function code(N)
	return Float64(Float64(Float64(Float64(-0.5 + Float64(Float64(0.3333333333333333 + Float64(-0.25 / N)) / N)) / N) + 1.0) / N)
end
function tmp = code(N)
	tmp = (((-0.5 + ((0.3333333333333333 + (-0.25 / N)) / N)) / N) + 1.0) / N;
end
code[N_] := N[(N[(N[(N[(-0.5 + N[(N[(0.3333333333333333 + N[(-0.25 / N), $MachinePrecision]), $MachinePrecision] / N), $MachinePrecision]), $MachinePrecision] / N), $MachinePrecision] + 1.0), $MachinePrecision] / N), $MachinePrecision]
\begin{array}{l}

\\
\frac{\frac{-0.5 + \frac{0.3333333333333333 + \frac{-0.25}{N}}{N}}{N} + 1}{N}
\end{array}
Derivation
  1. Initial program 23.4%

    \[\log \left(N + 1\right) - \log N \]
  2. Step-by-step derivation
    1. +-commutative23.4%

      \[\leadsto \log \color{blue}{\left(1 + N\right)} - \log N \]
    2. log1p-define23.4%

      \[\leadsto \color{blue}{\mathsf{log1p}\left(N\right)} - \log N \]
  3. Simplified23.4%

    \[\leadsto \color{blue}{\mathsf{log1p}\left(N\right) - \log N} \]
  4. Add Preprocessing
  5. Taylor expanded in N around -inf 96.1%

    \[\leadsto \color{blue}{-1 \cdot \frac{-1 \cdot \frac{-1 \cdot \frac{0.25 \cdot \frac{1}{N} - 0.3333333333333333}{N} - 0.5}{N} - 1}{N}} \]
  6. Step-by-step derivation
    1. mul-1-neg96.1%

      \[\leadsto \color{blue}{-\frac{-1 \cdot \frac{-1 \cdot \frac{0.25 \cdot \frac{1}{N} - 0.3333333333333333}{N} - 0.5}{N} - 1}{N}} \]
    2. distribute-neg-frac296.1%

      \[\leadsto \color{blue}{\frac{-1 \cdot \frac{-1 \cdot \frac{0.25 \cdot \frac{1}{N} - 0.3333333333333333}{N} - 0.5}{N} - 1}{-N}} \]
  7. Simplified96.1%

    \[\leadsto \color{blue}{\frac{-1 - \frac{-0.5 + \frac{0.3333333333333333 + \frac{-0.25}{N}}{N}}{N}}{-N}} \]
  8. Taylor expanded in N around -inf 96.1%

    \[\leadsto \color{blue}{-1 \cdot \frac{-1 \cdot \frac{-1 \cdot \frac{0.25 \cdot \frac{1}{N} - 0.3333333333333333}{N} - 0.5}{N} - 1}{N}} \]
  9. Simplified96.1%

    \[\leadsto \color{blue}{\frac{\frac{\frac{0.3333333333333333 + \frac{-0.25}{N}}{N} + -0.5}{N} + 1}{N}} \]
  10. Final simplification96.1%

    \[\leadsto \frac{\frac{-0.5 + \frac{0.3333333333333333 + \frac{-0.25}{N}}{N}}{N} + 1}{N} \]
  11. Add Preprocessing

Alternative 6: 94.9% accurate, 18.6× speedup?

\[\begin{array}{l} \\ \frac{\frac{-0.5 + \frac{0.3333333333333333}{N}}{N} + 1}{N} \end{array} \]
(FPCore (N)
 :precision binary64
 (/ (+ (/ (+ -0.5 (/ 0.3333333333333333 N)) N) 1.0) N))
double code(double N) {
	return (((-0.5 + (0.3333333333333333 / N)) / N) + 1.0) / N;
}
real(8) function code(n)
    real(8), intent (in) :: n
    code = ((((-0.5d0) + (0.3333333333333333d0 / n)) / n) + 1.0d0) / n
end function
public static double code(double N) {
	return (((-0.5 + (0.3333333333333333 / N)) / N) + 1.0) / N;
}
def code(N):
	return (((-0.5 + (0.3333333333333333 / N)) / N) + 1.0) / N
function code(N)
	return Float64(Float64(Float64(Float64(-0.5 + Float64(0.3333333333333333 / N)) / N) + 1.0) / N)
end
function tmp = code(N)
	tmp = (((-0.5 + (0.3333333333333333 / N)) / N) + 1.0) / N;
end
code[N_] := N[(N[(N[(N[(-0.5 + N[(0.3333333333333333 / N), $MachinePrecision]), $MachinePrecision] / N), $MachinePrecision] + 1.0), $MachinePrecision] / N), $MachinePrecision]
\begin{array}{l}

\\
\frac{\frac{-0.5 + \frac{0.3333333333333333}{N}}{N} + 1}{N}
\end{array}
Derivation
  1. Initial program 23.4%

    \[\log \left(N + 1\right) - \log N \]
  2. Step-by-step derivation
    1. +-commutative23.4%

      \[\leadsto \log \color{blue}{\left(1 + N\right)} - \log N \]
    2. log1p-define23.4%

      \[\leadsto \color{blue}{\mathsf{log1p}\left(N\right)} - \log N \]
  3. Simplified23.4%

    \[\leadsto \color{blue}{\mathsf{log1p}\left(N\right) - \log N} \]
  4. Add Preprocessing
  5. Taylor expanded in N around inf 94.4%

    \[\leadsto \color{blue}{\frac{\left(1 + \frac{0.3333333333333333}{{N}^{2}}\right) - 0.5 \cdot \frac{1}{N}}{N}} \]
  6. Step-by-step derivation
    1. associate--l+94.4%

      \[\leadsto \frac{\color{blue}{1 + \left(\frac{0.3333333333333333}{{N}^{2}} - 0.5 \cdot \frac{1}{N}\right)}}{N} \]
    2. unpow294.4%

      \[\leadsto \frac{1 + \left(\frac{0.3333333333333333}{\color{blue}{N \cdot N}} - 0.5 \cdot \frac{1}{N}\right)}{N} \]
    3. associate-/r*94.4%

      \[\leadsto \frac{1 + \left(\color{blue}{\frac{\frac{0.3333333333333333}{N}}{N}} - 0.5 \cdot \frac{1}{N}\right)}{N} \]
    4. metadata-eval94.4%

      \[\leadsto \frac{1 + \left(\frac{\frac{\color{blue}{0.3333333333333333 \cdot 1}}{N}}{N} - 0.5 \cdot \frac{1}{N}\right)}{N} \]
    5. associate-*r/94.4%

      \[\leadsto \frac{1 + \left(\frac{\color{blue}{0.3333333333333333 \cdot \frac{1}{N}}}{N} - 0.5 \cdot \frac{1}{N}\right)}{N} \]
    6. associate-*r/94.4%

      \[\leadsto \frac{1 + \left(\frac{0.3333333333333333 \cdot \frac{1}{N}}{N} - \color{blue}{\frac{0.5 \cdot 1}{N}}\right)}{N} \]
    7. metadata-eval94.4%

      \[\leadsto \frac{1 + \left(\frac{0.3333333333333333 \cdot \frac{1}{N}}{N} - \frac{\color{blue}{0.5}}{N}\right)}{N} \]
    8. div-sub94.4%

      \[\leadsto \frac{1 + \color{blue}{\frac{0.3333333333333333 \cdot \frac{1}{N} - 0.5}{N}}}{N} \]
    9. sub-neg94.4%

      \[\leadsto \frac{1 + \frac{\color{blue}{0.3333333333333333 \cdot \frac{1}{N} + \left(-0.5\right)}}{N}}{N} \]
    10. metadata-eval94.4%

      \[\leadsto \frac{1 + \frac{0.3333333333333333 \cdot \frac{1}{N} + \color{blue}{-0.5}}{N}}{N} \]
    11. +-commutative94.4%

      \[\leadsto \frac{1 + \frac{\color{blue}{-0.5 + 0.3333333333333333 \cdot \frac{1}{N}}}{N}}{N} \]
    12. associate-*r/94.4%

      \[\leadsto \frac{1 + \frac{-0.5 + \color{blue}{\frac{0.3333333333333333 \cdot 1}{N}}}{N}}{N} \]
    13. metadata-eval94.4%

      \[\leadsto \frac{1 + \frac{-0.5 + \frac{\color{blue}{0.3333333333333333}}{N}}{N}}{N} \]
  7. Simplified94.4%

    \[\leadsto \color{blue}{\frac{1 + \frac{-0.5 + \frac{0.3333333333333333}{N}}{N}}{N}} \]
  8. Final simplification94.4%

    \[\leadsto \frac{\frac{-0.5 + \frac{0.3333333333333333}{N}}{N} + 1}{N} \]
  9. Add Preprocessing

Alternative 7: 92.3% accurate, 22.8× speedup?

\[\begin{array}{l} \\ \frac{-1}{\frac{N}{-1 - \frac{-0.5}{N}}} \end{array} \]
(FPCore (N) :precision binary64 (/ -1.0 (/ N (- -1.0 (/ -0.5 N)))))
double code(double N) {
	return -1.0 / (N / (-1.0 - (-0.5 / N)));
}
real(8) function code(n)
    real(8), intent (in) :: n
    code = (-1.0d0) / (n / ((-1.0d0) - ((-0.5d0) / n)))
end function
public static double code(double N) {
	return -1.0 / (N / (-1.0 - (-0.5 / N)));
}
def code(N):
	return -1.0 / (N / (-1.0 - (-0.5 / N)))
function code(N)
	return Float64(-1.0 / Float64(N / Float64(-1.0 - Float64(-0.5 / N))))
end
function tmp = code(N)
	tmp = -1.0 / (N / (-1.0 - (-0.5 / N)));
end
code[N_] := N[(-1.0 / N[(N / N[(-1.0 - N[(-0.5 / N), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{-1}{\frac{N}{-1 - \frac{-0.5}{N}}}
\end{array}
Derivation
  1. Initial program 23.4%

    \[\log \left(N + 1\right) - \log N \]
  2. Step-by-step derivation
    1. +-commutative23.4%

      \[\leadsto \log \color{blue}{\left(1 + N\right)} - \log N \]
    2. log1p-define23.4%

      \[\leadsto \color{blue}{\mathsf{log1p}\left(N\right)} - \log N \]
  3. Simplified23.4%

    \[\leadsto \color{blue}{\mathsf{log1p}\left(N\right) - \log N} \]
  4. Add Preprocessing
  5. Taylor expanded in N around -inf 96.1%

    \[\leadsto \color{blue}{-1 \cdot \frac{-1 \cdot \frac{-1 \cdot \frac{0.25 \cdot \frac{1}{N} - 0.3333333333333333}{N} - 0.5}{N} - 1}{N}} \]
  6. Step-by-step derivation
    1. mul-1-neg96.1%

      \[\leadsto \color{blue}{-\frac{-1 \cdot \frac{-1 \cdot \frac{0.25 \cdot \frac{1}{N} - 0.3333333333333333}{N} - 0.5}{N} - 1}{N}} \]
    2. distribute-neg-frac296.1%

      \[\leadsto \color{blue}{\frac{-1 \cdot \frac{-1 \cdot \frac{0.25 \cdot \frac{1}{N} - 0.3333333333333333}{N} - 0.5}{N} - 1}{-N}} \]
  7. Simplified96.1%

    \[\leadsto \color{blue}{\frac{-1 - \frac{-0.5 + \frac{0.3333333333333333 + \frac{-0.25}{N}}{N}}{N}}{-N}} \]
  8. Taylor expanded in N around -inf 91.8%

    \[\leadsto \color{blue}{-1 \cdot \frac{0.5 \cdot \frac{1}{N} - 1}{N}} \]
  9. Step-by-step derivation
    1. associate-*r/91.8%

      \[\leadsto \color{blue}{\frac{-1 \cdot \left(0.5 \cdot \frac{1}{N} - 1\right)}{N}} \]
    2. sub-neg91.8%

      \[\leadsto \frac{-1 \cdot \color{blue}{\left(0.5 \cdot \frac{1}{N} + \left(-1\right)\right)}}{N} \]
    3. metadata-eval91.8%

      \[\leadsto \frac{-1 \cdot \left(0.5 \cdot \frac{1}{N} + \color{blue}{-1}\right)}{N} \]
    4. distribute-lft-in91.8%

      \[\leadsto \frac{\color{blue}{-1 \cdot \left(0.5 \cdot \frac{1}{N}\right) + -1 \cdot -1}}{N} \]
    5. neg-mul-191.8%

      \[\leadsto \frac{\color{blue}{\left(-0.5 \cdot \frac{1}{N}\right)} + -1 \cdot -1}{N} \]
    6. associate-*r/91.8%

      \[\leadsto \frac{\left(-\color{blue}{\frac{0.5 \cdot 1}{N}}\right) + -1 \cdot -1}{N} \]
    7. metadata-eval91.8%

      \[\leadsto \frac{\left(-\frac{\color{blue}{0.5}}{N}\right) + -1 \cdot -1}{N} \]
    8. distribute-neg-frac91.8%

      \[\leadsto \frac{\color{blue}{\frac{-0.5}{N}} + -1 \cdot -1}{N} \]
    9. metadata-eval91.8%

      \[\leadsto \frac{\frac{\color{blue}{-0.5}}{N} + -1 \cdot -1}{N} \]
    10. metadata-eval91.8%

      \[\leadsto \frac{\frac{-0.5}{N} + \color{blue}{1}}{N} \]
  10. Simplified91.8%

    \[\leadsto \color{blue}{\frac{\frac{-0.5}{N} + 1}{N}} \]
  11. Step-by-step derivation
    1. clear-num91.8%

      \[\leadsto \color{blue}{\frac{1}{\frac{N}{\frac{-0.5}{N} + 1}}} \]
  12. Applied egg-rr91.8%

    \[\leadsto \color{blue}{\frac{1}{\frac{N}{\frac{-0.5}{N} + 1}}} \]
  13. Final simplification91.8%

    \[\leadsto \frac{-1}{\frac{N}{-1 - \frac{-0.5}{N}}} \]
  14. Add Preprocessing

Alternative 8: 92.3% accurate, 29.3× speedup?

\[\begin{array}{l} \\ \frac{\frac{-0.5}{N} + 1}{N} \end{array} \]
(FPCore (N) :precision binary64 (/ (+ (/ -0.5 N) 1.0) N))
double code(double N) {
	return ((-0.5 / N) + 1.0) / N;
}
real(8) function code(n)
    real(8), intent (in) :: n
    code = (((-0.5d0) / n) + 1.0d0) / n
end function
public static double code(double N) {
	return ((-0.5 / N) + 1.0) / N;
}
def code(N):
	return ((-0.5 / N) + 1.0) / N
function code(N)
	return Float64(Float64(Float64(-0.5 / N) + 1.0) / N)
end
function tmp = code(N)
	tmp = ((-0.5 / N) + 1.0) / N;
end
code[N_] := N[(N[(N[(-0.5 / N), $MachinePrecision] + 1.0), $MachinePrecision] / N), $MachinePrecision]
\begin{array}{l}

\\
\frac{\frac{-0.5}{N} + 1}{N}
\end{array}
Derivation
  1. Initial program 23.4%

    \[\log \left(N + 1\right) - \log N \]
  2. Step-by-step derivation
    1. +-commutative23.4%

      \[\leadsto \log \color{blue}{\left(1 + N\right)} - \log N \]
    2. log1p-define23.4%

      \[\leadsto \color{blue}{\mathsf{log1p}\left(N\right)} - \log N \]
  3. Simplified23.4%

    \[\leadsto \color{blue}{\mathsf{log1p}\left(N\right) - \log N} \]
  4. Add Preprocessing
  5. Taylor expanded in N around inf 91.8%

    \[\leadsto \color{blue}{\frac{1 - 0.5 \cdot \frac{1}{N}}{N}} \]
  6. Step-by-step derivation
    1. sub-neg91.8%

      \[\leadsto \frac{\color{blue}{1 + \left(-0.5 \cdot \frac{1}{N}\right)}}{N} \]
    2. +-commutative91.8%

      \[\leadsto \frac{\color{blue}{\left(-0.5 \cdot \frac{1}{N}\right) + 1}}{N} \]
    3. neg-sub091.8%

      \[\leadsto \frac{\color{blue}{\left(0 - 0.5 \cdot \frac{1}{N}\right)} + 1}{N} \]
    4. associate-+l-91.8%

      \[\leadsto \frac{\color{blue}{0 - \left(0.5 \cdot \frac{1}{N} - 1\right)}}{N} \]
    5. neg-sub091.8%

      \[\leadsto \frac{\color{blue}{-\left(0.5 \cdot \frac{1}{N} - 1\right)}}{N} \]
    6. mul-1-neg91.8%

      \[\leadsto \frac{\color{blue}{-1 \cdot \left(0.5 \cdot \frac{1}{N} - 1\right)}}{N} \]
    7. mul-1-neg91.8%

      \[\leadsto \frac{\color{blue}{-\left(0.5 \cdot \frac{1}{N} - 1\right)}}{N} \]
    8. neg-sub091.8%

      \[\leadsto \frac{\color{blue}{0 - \left(0.5 \cdot \frac{1}{N} - 1\right)}}{N} \]
    9. associate-+l-91.8%

      \[\leadsto \frac{\color{blue}{\left(0 - 0.5 \cdot \frac{1}{N}\right) + 1}}{N} \]
    10. neg-sub091.8%

      \[\leadsto \frac{\color{blue}{\left(-0.5 \cdot \frac{1}{N}\right)} + 1}{N} \]
    11. +-commutative91.8%

      \[\leadsto \frac{\color{blue}{1 + \left(-0.5 \cdot \frac{1}{N}\right)}}{N} \]
    12. associate-*r/91.8%

      \[\leadsto \frac{1 + \left(-\color{blue}{\frac{0.5 \cdot 1}{N}}\right)}{N} \]
    13. metadata-eval91.8%

      \[\leadsto \frac{1 + \left(-\frac{\color{blue}{0.5}}{N}\right)}{N} \]
    14. distribute-neg-frac91.8%

      \[\leadsto \frac{1 + \color{blue}{\frac{-0.5}{N}}}{N} \]
    15. metadata-eval91.8%

      \[\leadsto \frac{1 + \frac{\color{blue}{-0.5}}{N}}{N} \]
  7. Simplified91.8%

    \[\leadsto \color{blue}{\frac{1 + \frac{-0.5}{N}}{N}} \]
  8. Final simplification91.8%

    \[\leadsto \frac{\frac{-0.5}{N} + 1}{N} \]
  9. Add Preprocessing

Alternative 9: 84.6% accurate, 68.3× speedup?

\[\begin{array}{l} \\ \frac{1}{N} \end{array} \]
(FPCore (N) :precision binary64 (/ 1.0 N))
double code(double N) {
	return 1.0 / N;
}
real(8) function code(n)
    real(8), intent (in) :: n
    code = 1.0d0 / n
end function
public static double code(double N) {
	return 1.0 / N;
}
def code(N):
	return 1.0 / N
function code(N)
	return Float64(1.0 / N)
end
function tmp = code(N)
	tmp = 1.0 / N;
end
code[N_] := N[(1.0 / N), $MachinePrecision]
\begin{array}{l}

\\
\frac{1}{N}
\end{array}
Derivation
  1. Initial program 23.4%

    \[\log \left(N + 1\right) - \log N \]
  2. Step-by-step derivation
    1. +-commutative23.4%

      \[\leadsto \log \color{blue}{\left(1 + N\right)} - \log N \]
    2. log1p-define23.4%

      \[\leadsto \color{blue}{\mathsf{log1p}\left(N\right)} - \log N \]
  3. Simplified23.4%

    \[\leadsto \color{blue}{\mathsf{log1p}\left(N\right) - \log N} \]
  4. Add Preprocessing
  5. Taylor expanded in N around inf 85.0%

    \[\leadsto \color{blue}{\frac{1}{N}} \]
  6. Add Preprocessing

Developer target: 99.8% accurate, 2.0× speedup?

\[\begin{array}{l} \\ \mathsf{log1p}\left(\frac{1}{N}\right) \end{array} \]
(FPCore (N) :precision binary64 (log1p (/ 1.0 N)))
double code(double N) {
	return log1p((1.0 / N));
}
public static double code(double N) {
	return Math.log1p((1.0 / N));
}
def code(N):
	return math.log1p((1.0 / N))
function code(N)
	return log1p(Float64(1.0 / N))
end
code[N_] := N[Log[1 + N[(1.0 / N), $MachinePrecision]], $MachinePrecision]
\begin{array}{l}

\\
\mathsf{log1p}\left(\frac{1}{N}\right)
\end{array}

Reproduce

?
herbie shell --seed 2024095 
(FPCore (N)
  :name "2log (problem 3.3.6)"
  :precision binary64
  :pre (and (> N 1.0) (< N 1e+40))

  :alt
  (log1p (/ 1.0 N))

  (- (log (+ N 1.0)) (log N)))