2log (problem 3.3.6)

Percentage Accurate: 24.2% → 99.8%
Time: 7.8s
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: 24.2% 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: 99.8% 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}
Derivation
  1. Initial program 26.4%

    \[\log \left(N + 1\right) - \log N \]
  2. Add Preprocessing
  3. Step-by-step derivation
    1. diff-log28.8%

      \[\leadsto \color{blue}{\log \left(\frac{N + 1}{N}\right)} \]
  4. Applied egg-rr28.8%

    \[\leadsto \color{blue}{\log \left(\frac{N + 1}{N}\right)} \]
  5. Step-by-step derivation
    1. *-lft-identity28.8%

      \[\leadsto \log \left(\frac{\color{blue}{1 \cdot \left(N + 1\right)}}{N}\right) \]
    2. associate-*l/28.5%

      \[\leadsto \log \color{blue}{\left(\frac{1}{N} \cdot \left(N + 1\right)\right)} \]
    3. distribute-lft-in28.6%

      \[\leadsto \log \color{blue}{\left(\frac{1}{N} \cdot N + \frac{1}{N} \cdot 1\right)} \]
    4. lft-mult-inverse28.8%

      \[\leadsto \log \left(\color{blue}{1} + \frac{1}{N} \cdot 1\right) \]
    5. *-rgt-identity28.8%

      \[\leadsto \log \left(1 + \color{blue}{\frac{1}{N}}\right) \]
    6. log1p-define99.8%

      \[\leadsto \color{blue}{\mathsf{log1p}\left(\frac{1}{N}\right)} \]
  6. Simplified99.8%

    \[\leadsto \color{blue}{\mathsf{log1p}\left(\frac{1}{N}\right)} \]
  7. Add Preprocessing

Alternative 2: 96.2% accurate, 12.1× speedup?

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

\\
\frac{-1}{\frac{N}{\frac{0.5 - \frac{0.3333333333333333 + \frac{-0.25}{N}}{N}}{N} + -1}}
\end{array}
Derivation
  1. Initial program 26.4%

    \[\log \left(N + 1\right) - \log N \]
  2. Add Preprocessing
  3. Step-by-step derivation
    1. diff-log28.8%

      \[\leadsto \color{blue}{\log \left(\frac{N + 1}{N}\right)} \]
  4. Applied egg-rr28.8%

    \[\leadsto \color{blue}{\log \left(\frac{N + 1}{N}\right)} \]
  5. Step-by-step derivation
    1. *-lft-identity28.8%

      \[\leadsto \log \left(\frac{\color{blue}{1 \cdot \left(N + 1\right)}}{N}\right) \]
    2. associate-*l/28.5%

      \[\leadsto \log \color{blue}{\left(\frac{1}{N} \cdot \left(N + 1\right)\right)} \]
    3. distribute-lft-in28.6%

      \[\leadsto \log \color{blue}{\left(\frac{1}{N} \cdot N + \frac{1}{N} \cdot 1\right)} \]
    4. lft-mult-inverse28.8%

      \[\leadsto \log \left(\color{blue}{1} + \frac{1}{N} \cdot 1\right) \]
    5. *-rgt-identity28.8%

      \[\leadsto \log \left(1 + \color{blue}{\frac{1}{N}}\right) \]
    6. log1p-define99.8%

      \[\leadsto \color{blue}{\mathsf{log1p}\left(\frac{1}{N}\right)} \]
  6. Simplified99.8%

    \[\leadsto \color{blue}{\mathsf{log1p}\left(\frac{1}{N}\right)} \]
  7. Step-by-step derivation
    1. add-sqr-sqrt99.2%

      \[\leadsto \mathsf{log1p}\left(\color{blue}{\sqrt{\frac{1}{N}} \cdot \sqrt{\frac{1}{N}}}\right) \]
    2. sqrt-unprod99.8%

      \[\leadsto \mathsf{log1p}\left(\color{blue}{\sqrt{\frac{1}{N} \cdot \frac{1}{N}}}\right) \]
    3. inv-pow99.8%

      \[\leadsto \mathsf{log1p}\left(\sqrt{\color{blue}{{N}^{-1}} \cdot \frac{1}{N}}\right) \]
    4. inv-pow99.8%

      \[\leadsto \mathsf{log1p}\left(\sqrt{{N}^{-1} \cdot \color{blue}{{N}^{-1}}}\right) \]
    5. pow-prod-up99.7%

      \[\leadsto \mathsf{log1p}\left(\sqrt{\color{blue}{{N}^{\left(-1 + -1\right)}}}\right) \]
    6. metadata-eval99.7%

      \[\leadsto \mathsf{log1p}\left(\sqrt{{N}^{\color{blue}{-2}}}\right) \]
  8. Applied egg-rr99.7%

    \[\leadsto \mathsf{log1p}\left(\color{blue}{\sqrt{{N}^{-2}}}\right) \]
  9. Taylor expanded in N around inf 95.6%

    \[\leadsto \color{blue}{\frac{\left(1 + \frac{0.3333333333333333}{{N}^{2}}\right) - \left(0.5 \cdot \frac{1}{N} + 0.25 \cdot \frac{1}{{N}^{3}}\right)}{N}} \]
  10. Simplified95.6%

    \[\leadsto \color{blue}{\frac{1 + \frac{-0.5 + \frac{0.3333333333333333 + \frac{-0.25}{N}}{N}}{N}}{N}} \]
  11. Step-by-step derivation
    1. clear-num95.6%

      \[\leadsto \color{blue}{\frac{1}{\frac{N}{1 + \frac{-0.5 + \frac{0.3333333333333333 + \frac{-0.25}{N}}{N}}{N}}}} \]
    2. inv-pow95.6%

      \[\leadsto \color{blue}{{\left(\frac{N}{1 + \frac{-0.5 + \frac{0.3333333333333333 + \frac{-0.25}{N}}{N}}{N}}\right)}^{-1}} \]
  12. Applied egg-rr95.6%

    \[\leadsto \color{blue}{{\left(\frac{N}{1 + \frac{-0.5 + \frac{0.3333333333333333 + \frac{-0.25}{N}}{N}}{N}}\right)}^{-1}} \]
  13. Simplified95.6%

    \[\leadsto \color{blue}{\frac{1}{\frac{N}{1 - \frac{0.5 - \frac{0.3333333333333333 + \frac{-0.25}{N}}{N}}{N}}}} \]
  14. Final simplification95.6%

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

Alternative 3: 96.1% accurate, 13.7× speedup?

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

\\
\frac{\frac{\frac{0.3333333333333333 + \frac{-0.25}{N}}{N} + -0.5}{N} + 1}{N}
\end{array}
Derivation
  1. Initial program 26.4%

    \[\log \left(N + 1\right) - \log N \]
  2. Add Preprocessing
  3. Step-by-step derivation
    1. diff-log28.8%

      \[\leadsto \color{blue}{\log \left(\frac{N + 1}{N}\right)} \]
  4. Applied egg-rr28.8%

    \[\leadsto \color{blue}{\log \left(\frac{N + 1}{N}\right)} \]
  5. Step-by-step derivation
    1. *-lft-identity28.8%

      \[\leadsto \log \left(\frac{\color{blue}{1 \cdot \left(N + 1\right)}}{N}\right) \]
    2. associate-*l/28.5%

      \[\leadsto \log \color{blue}{\left(\frac{1}{N} \cdot \left(N + 1\right)\right)} \]
    3. distribute-lft-in28.6%

      \[\leadsto \log \color{blue}{\left(\frac{1}{N} \cdot N + \frac{1}{N} \cdot 1\right)} \]
    4. lft-mult-inverse28.8%

      \[\leadsto \log \left(\color{blue}{1} + \frac{1}{N} \cdot 1\right) \]
    5. *-rgt-identity28.8%

      \[\leadsto \log \left(1 + \color{blue}{\frac{1}{N}}\right) \]
    6. log1p-define99.8%

      \[\leadsto \color{blue}{\mathsf{log1p}\left(\frac{1}{N}\right)} \]
  6. Simplified99.8%

    \[\leadsto \color{blue}{\mathsf{log1p}\left(\frac{1}{N}\right)} \]
  7. Step-by-step derivation
    1. add-sqr-sqrt99.2%

      \[\leadsto \mathsf{log1p}\left(\color{blue}{\sqrt{\frac{1}{N}} \cdot \sqrt{\frac{1}{N}}}\right) \]
    2. sqrt-unprod99.8%

      \[\leadsto \mathsf{log1p}\left(\color{blue}{\sqrt{\frac{1}{N} \cdot \frac{1}{N}}}\right) \]
    3. inv-pow99.8%

      \[\leadsto \mathsf{log1p}\left(\sqrt{\color{blue}{{N}^{-1}} \cdot \frac{1}{N}}\right) \]
    4. inv-pow99.8%

      \[\leadsto \mathsf{log1p}\left(\sqrt{{N}^{-1} \cdot \color{blue}{{N}^{-1}}}\right) \]
    5. pow-prod-up99.7%

      \[\leadsto \mathsf{log1p}\left(\sqrt{\color{blue}{{N}^{\left(-1 + -1\right)}}}\right) \]
    6. metadata-eval99.7%

      \[\leadsto \mathsf{log1p}\left(\sqrt{{N}^{\color{blue}{-2}}}\right) \]
  8. Applied egg-rr99.7%

    \[\leadsto \mathsf{log1p}\left(\color{blue}{\sqrt{{N}^{-2}}}\right) \]
  9. Taylor expanded in N around inf 95.6%

    \[\leadsto \color{blue}{\frac{\left(1 + \frac{0.3333333333333333}{{N}^{2}}\right) - \left(0.5 \cdot \frac{1}{N} + 0.25 \cdot \frac{1}{{N}^{3}}\right)}{N}} \]
  10. Simplified95.6%

    \[\leadsto \color{blue}{\frac{1 + \frac{-0.5 + \frac{0.3333333333333333 + \frac{-0.25}{N}}{N}}{N}}{N}} \]
  11. Final simplification95.6%

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

Alternative 4: 95.4% accurate, 15.8× speedup?

\[\begin{array}{l} \\ \frac{1}{N + N \cdot \frac{0.5 + \frac{-0.08333333333333333}{N}}{N}} \end{array} \]
(FPCore (N)
 :precision binary64
 (/ 1.0 (+ N (* N (/ (+ 0.5 (/ -0.08333333333333333 N)) N)))))
double code(double N) {
	return 1.0 / (N + (N * ((0.5 + (-0.08333333333333333 / N)) / N)));
}
real(8) function code(n)
    real(8), intent (in) :: n
    code = 1.0d0 / (n + (n * ((0.5d0 + ((-0.08333333333333333d0) / n)) / n)))
end function
public static double code(double N) {
	return 1.0 / (N + (N * ((0.5 + (-0.08333333333333333 / N)) / N)));
}
def code(N):
	return 1.0 / (N + (N * ((0.5 + (-0.08333333333333333 / N)) / N)))
function code(N)
	return Float64(1.0 / Float64(N + Float64(N * Float64(Float64(0.5 + Float64(-0.08333333333333333 / N)) / N))))
end
function tmp = code(N)
	tmp = 1.0 / (N + (N * ((0.5 + (-0.08333333333333333 / N)) / N)));
end
code[N_] := N[(1.0 / N[(N + N[(N * N[(N[(0.5 + N[(-0.08333333333333333 / N), $MachinePrecision]), $MachinePrecision] / N), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{1}{N + N \cdot \frac{0.5 + \frac{-0.08333333333333333}{N}}{N}}
\end{array}
Derivation
  1. Initial program 26.4%

    \[\log \left(N + 1\right) - \log N \]
  2. Add Preprocessing
  3. Taylor expanded in N around inf 94.2%

    \[\leadsto \color{blue}{\frac{\left(1 + \frac{0.3333333333333333}{{N}^{2}}\right) - 0.5 \cdot \frac{1}{N}}{N}} \]
  4. Step-by-step derivation
    1. associate--l+94.2%

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

      \[\leadsto \frac{1 + \left(\frac{0.3333333333333333}{\color{blue}{N \cdot N}} - 0.5 \cdot \frac{1}{N}\right)}{N} \]
    3. associate-/r*94.2%

      \[\leadsto \frac{1 + \left(\color{blue}{\frac{\frac{0.3333333333333333}{N}}{N}} - 0.5 \cdot \frac{1}{N}\right)}{N} \]
    4. metadata-eval94.2%

      \[\leadsto \frac{1 + \left(\frac{\frac{\color{blue}{0.3333333333333333 \cdot 1}}{N}}{N} - 0.5 \cdot \frac{1}{N}\right)}{N} \]
    5. associate-*r/94.2%

      \[\leadsto \frac{1 + \left(\frac{\color{blue}{0.3333333333333333 \cdot \frac{1}{N}}}{N} - 0.5 \cdot \frac{1}{N}\right)}{N} \]
    6. associate-*r/94.2%

      \[\leadsto \frac{1 + \left(\frac{0.3333333333333333 \cdot \frac{1}{N}}{N} - \color{blue}{\frac{0.5 \cdot 1}{N}}\right)}{N} \]
    7. metadata-eval94.2%

      \[\leadsto \frac{1 + \left(\frac{0.3333333333333333 \cdot \frac{1}{N}}{N} - \frac{\color{blue}{0.5}}{N}\right)}{N} \]
    8. div-sub94.2%

      \[\leadsto \frac{1 + \color{blue}{\frac{0.3333333333333333 \cdot \frac{1}{N} - 0.5}{N}}}{N} \]
    9. sub-neg94.2%

      \[\leadsto \frac{1 + \frac{\color{blue}{0.3333333333333333 \cdot \frac{1}{N} + \left(-0.5\right)}}{N}}{N} \]
    10. metadata-eval94.2%

      \[\leadsto \frac{1 + \frac{0.3333333333333333 \cdot \frac{1}{N} + \color{blue}{-0.5}}{N}}{N} \]
    11. +-commutative94.2%

      \[\leadsto \frac{1 + \frac{\color{blue}{-0.5 + 0.3333333333333333 \cdot \frac{1}{N}}}{N}}{N} \]
    12. associate-*r/94.2%

      \[\leadsto \frac{1 + \frac{-0.5 + \color{blue}{\frac{0.3333333333333333 \cdot 1}{N}}}{N}}{N} \]
    13. metadata-eval94.2%

      \[\leadsto \frac{1 + \frac{-0.5 + \frac{\color{blue}{0.3333333333333333}}{N}}{N}}{N} \]
  5. Simplified94.2%

    \[\leadsto \color{blue}{\frac{1 + \frac{-0.5 + \frac{0.3333333333333333}{N}}{N}}{N}} \]
  6. Step-by-step derivation
    1. clear-num94.2%

      \[\leadsto \color{blue}{\frac{1}{\frac{N}{1 + \frac{-0.5 + \frac{0.3333333333333333}{N}}{N}}}} \]
    2. inv-pow94.2%

      \[\leadsto \color{blue}{{\left(\frac{N}{1 + \frac{-0.5 + \frac{0.3333333333333333}{N}}{N}}\right)}^{-1}} \]
  7. Applied egg-rr94.2%

    \[\leadsto \color{blue}{{\left(\frac{N}{1 + \frac{-0.5 + \frac{0.3333333333333333}{N}}{N}}\right)}^{-1}} \]
  8. Step-by-step derivation
    1. unpow-194.2%

      \[\leadsto \color{blue}{\frac{1}{\frac{N}{1 + \frac{-0.5 + \frac{0.3333333333333333}{N}}{N}}}} \]
    2. remove-double-neg94.2%

      \[\leadsto \frac{1}{\frac{N}{1 + \color{blue}{\left(-\left(-\frac{-0.5 + \frac{0.3333333333333333}{N}}{N}\right)\right)}}} \]
    3. neg-mul-194.2%

      \[\leadsto \frac{1}{\frac{N}{1 + \left(-\color{blue}{-1 \cdot \frac{-0.5 + \frac{0.3333333333333333}{N}}{N}}\right)}} \]
    4. associate-*r/94.2%

      \[\leadsto \frac{1}{\frac{N}{1 + \left(-\color{blue}{\frac{-1 \cdot \left(-0.5 + \frac{0.3333333333333333}{N}\right)}{N}}\right)}} \]
    5. neg-mul-194.2%

      \[\leadsto \frac{1}{\frac{N}{1 + \left(-\frac{\color{blue}{-\left(-0.5 + \frac{0.3333333333333333}{N}\right)}}{N}\right)}} \]
    6. distribute-neg-in94.2%

      \[\leadsto \frac{1}{\frac{N}{1 + \left(-\frac{\color{blue}{\left(--0.5\right) + \left(-\frac{0.3333333333333333}{N}\right)}}{N}\right)}} \]
    7. metadata-eval94.2%

      \[\leadsto \frac{1}{\frac{N}{1 + \left(-\frac{\color{blue}{0.5} + \left(-\frac{0.3333333333333333}{N}\right)}{N}\right)}} \]
    8. metadata-eval94.2%

      \[\leadsto \frac{1}{\frac{N}{1 + \left(-\frac{0.5 + \left(-\frac{\color{blue}{0.3333333333333333 \cdot 1}}{N}\right)}{N}\right)}} \]
    9. associate-*r/94.2%

      \[\leadsto \frac{1}{\frac{N}{1 + \left(-\frac{0.5 + \left(-\color{blue}{0.3333333333333333 \cdot \frac{1}{N}}\right)}{N}\right)}} \]
    10. sub-neg94.2%

      \[\leadsto \frac{1}{\frac{N}{1 + \left(-\frac{\color{blue}{0.5 - 0.3333333333333333 \cdot \frac{1}{N}}}{N}\right)}} \]
    11. associate-*r/94.2%

      \[\leadsto \frac{1}{\frac{N}{1 + \left(-\frac{0.5 - \color{blue}{\frac{0.3333333333333333 \cdot 1}{N}}}{N}\right)}} \]
    12. metadata-eval94.2%

      \[\leadsto \frac{1}{\frac{N}{1 + \left(-\frac{0.5 - \frac{\color{blue}{0.3333333333333333}}{N}}{N}\right)}} \]
    13. unsub-neg94.2%

      \[\leadsto \frac{1}{\frac{N}{1 + \left(-\frac{\color{blue}{0.5 + \left(-\frac{0.3333333333333333}{N}\right)}}{N}\right)}} \]
    14. unsub-neg94.2%

      \[\leadsto \frac{1}{\frac{N}{\color{blue}{1 - \frac{0.5 + \left(-\frac{0.3333333333333333}{N}\right)}{N}}}} \]
    15. unsub-neg94.2%

      \[\leadsto \frac{1}{\frac{N}{1 - \frac{\color{blue}{0.5 - \frac{0.3333333333333333}{N}}}{N}}} \]
  9. Simplified94.2%

    \[\leadsto \color{blue}{\frac{1}{\frac{N}{1 - \frac{0.5 + \frac{-0.3333333333333333}{N}}{N}}}} \]
  10. Taylor expanded in N around inf 94.7%

    \[\leadsto \frac{1}{\color{blue}{N \cdot \left(\left(1 + 0.5 \cdot \frac{1}{N}\right) - \frac{0.08333333333333333}{{N}^{2}}\right)}} \]
  11. Step-by-step derivation
    1. associate--l+94.7%

      \[\leadsto \frac{1}{N \cdot \color{blue}{\left(1 + \left(0.5 \cdot \frac{1}{N} - \frac{0.08333333333333333}{{N}^{2}}\right)\right)}} \]
    2. associate-*r/94.7%

      \[\leadsto \frac{1}{N \cdot \left(1 + \left(\color{blue}{\frac{0.5 \cdot 1}{N}} - \frac{0.08333333333333333}{{N}^{2}}\right)\right)} \]
    3. metadata-eval94.7%

      \[\leadsto \frac{1}{N \cdot \left(1 + \left(\frac{\color{blue}{0.5}}{N} - \frac{0.08333333333333333}{{N}^{2}}\right)\right)} \]
    4. unpow294.7%

      \[\leadsto \frac{1}{N \cdot \left(1 + \left(\frac{0.5}{N} - \frac{0.08333333333333333}{\color{blue}{N \cdot N}}\right)\right)} \]
    5. associate-/r*94.7%

      \[\leadsto \frac{1}{N \cdot \left(1 + \left(\frac{0.5}{N} - \color{blue}{\frac{\frac{0.08333333333333333}{N}}{N}}\right)\right)} \]
    6. metadata-eval94.7%

      \[\leadsto \frac{1}{N \cdot \left(1 + \left(\frac{0.5}{N} - \frac{\frac{\color{blue}{0.08333333333333333 \cdot 1}}{N}}{N}\right)\right)} \]
    7. associate-*r/94.7%

      \[\leadsto \frac{1}{N \cdot \left(1 + \left(\frac{0.5}{N} - \frac{\color{blue}{0.08333333333333333 \cdot \frac{1}{N}}}{N}\right)\right)} \]
    8. div-sub94.7%

      \[\leadsto \frac{1}{N \cdot \left(1 + \color{blue}{\frac{0.5 - 0.08333333333333333 \cdot \frac{1}{N}}{N}}\right)} \]
    9. cancel-sign-sub-inv94.7%

      \[\leadsto \frac{1}{N \cdot \left(1 + \frac{\color{blue}{0.5 + \left(-0.08333333333333333\right) \cdot \frac{1}{N}}}{N}\right)} \]
    10. associate-*r/94.7%

      \[\leadsto \frac{1}{N \cdot \left(1 + \frac{0.5 + \color{blue}{\frac{\left(-0.08333333333333333\right) \cdot 1}{N}}}{N}\right)} \]
    11. metadata-eval94.7%

      \[\leadsto \frac{1}{N \cdot \left(1 + \frac{0.5 + \frac{\color{blue}{-0.08333333333333333} \cdot 1}{N}}{N}\right)} \]
    12. metadata-eval94.7%

      \[\leadsto \frac{1}{N \cdot \left(1 + \frac{0.5 + \frac{\color{blue}{-0.08333333333333333}}{N}}{N}\right)} \]
  12. Simplified94.7%

    \[\leadsto \frac{1}{\color{blue}{N \cdot \left(1 + \frac{0.5 + \frac{-0.08333333333333333}{N}}{N}\right)}} \]
  13. Step-by-step derivation
    1. +-commutative94.7%

      \[\leadsto \frac{1}{N \cdot \color{blue}{\left(\frac{0.5 + \frac{-0.08333333333333333}{N}}{N} + 1\right)}} \]
    2. distribute-rgt-in94.8%

      \[\leadsto \frac{1}{\color{blue}{\frac{0.5 + \frac{-0.08333333333333333}{N}}{N} \cdot N + 1 \cdot N}} \]
    3. *-un-lft-identity94.8%

      \[\leadsto \frac{1}{\frac{0.5 + \frac{-0.08333333333333333}{N}}{N} \cdot N + \color{blue}{N}} \]
  14. Applied egg-rr94.8%

    \[\leadsto \frac{1}{\color{blue}{\frac{0.5 + \frac{-0.08333333333333333}{N}}{N} \cdot N + N}} \]
  15. Final simplification94.8%

    \[\leadsto \frac{1}{N + N \cdot \frac{0.5 + \frac{-0.08333333333333333}{N}}{N}} \]
  16. Add Preprocessing

Alternative 5: 95.3% accurate, 15.8× speedup?

\[\begin{array}{l} \\ \frac{-1}{N \cdot \left(-1 - \frac{0.5 + \frac{-0.08333333333333333}{N}}{N}\right)} \end{array} \]
(FPCore (N)
 :precision binary64
 (/ -1.0 (* N (- -1.0 (/ (+ 0.5 (/ -0.08333333333333333 N)) N)))))
double code(double N) {
	return -1.0 / (N * (-1.0 - ((0.5 + (-0.08333333333333333 / N)) / N)));
}
real(8) function code(n)
    real(8), intent (in) :: n
    code = (-1.0d0) / (n * ((-1.0d0) - ((0.5d0 + ((-0.08333333333333333d0) / n)) / n)))
end function
public static double code(double N) {
	return -1.0 / (N * (-1.0 - ((0.5 + (-0.08333333333333333 / N)) / N)));
}
def code(N):
	return -1.0 / (N * (-1.0 - ((0.5 + (-0.08333333333333333 / N)) / N)))
function code(N)
	return Float64(-1.0 / Float64(N * Float64(-1.0 - Float64(Float64(0.5 + Float64(-0.08333333333333333 / N)) / N))))
end
function tmp = code(N)
	tmp = -1.0 / (N * (-1.0 - ((0.5 + (-0.08333333333333333 / N)) / N)));
end
code[N_] := N[(-1.0 / N[(N * N[(-1.0 - N[(N[(0.5 + N[(-0.08333333333333333 / N), $MachinePrecision]), $MachinePrecision] / N), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{-1}{N \cdot \left(-1 - \frac{0.5 + \frac{-0.08333333333333333}{N}}{N}\right)}
\end{array}
Derivation
  1. Initial program 26.4%

    \[\log \left(N + 1\right) - \log N \]
  2. Add Preprocessing
  3. Taylor expanded in N around inf 94.2%

    \[\leadsto \color{blue}{\frac{\left(1 + \frac{0.3333333333333333}{{N}^{2}}\right) - 0.5 \cdot \frac{1}{N}}{N}} \]
  4. Step-by-step derivation
    1. associate--l+94.2%

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

      \[\leadsto \frac{1 + \left(\frac{0.3333333333333333}{\color{blue}{N \cdot N}} - 0.5 \cdot \frac{1}{N}\right)}{N} \]
    3. associate-/r*94.2%

      \[\leadsto \frac{1 + \left(\color{blue}{\frac{\frac{0.3333333333333333}{N}}{N}} - 0.5 \cdot \frac{1}{N}\right)}{N} \]
    4. metadata-eval94.2%

      \[\leadsto \frac{1 + \left(\frac{\frac{\color{blue}{0.3333333333333333 \cdot 1}}{N}}{N} - 0.5 \cdot \frac{1}{N}\right)}{N} \]
    5. associate-*r/94.2%

      \[\leadsto \frac{1 + \left(\frac{\color{blue}{0.3333333333333333 \cdot \frac{1}{N}}}{N} - 0.5 \cdot \frac{1}{N}\right)}{N} \]
    6. associate-*r/94.2%

      \[\leadsto \frac{1 + \left(\frac{0.3333333333333333 \cdot \frac{1}{N}}{N} - \color{blue}{\frac{0.5 \cdot 1}{N}}\right)}{N} \]
    7. metadata-eval94.2%

      \[\leadsto \frac{1 + \left(\frac{0.3333333333333333 \cdot \frac{1}{N}}{N} - \frac{\color{blue}{0.5}}{N}\right)}{N} \]
    8. div-sub94.2%

      \[\leadsto \frac{1 + \color{blue}{\frac{0.3333333333333333 \cdot \frac{1}{N} - 0.5}{N}}}{N} \]
    9. sub-neg94.2%

      \[\leadsto \frac{1 + \frac{\color{blue}{0.3333333333333333 \cdot \frac{1}{N} + \left(-0.5\right)}}{N}}{N} \]
    10. metadata-eval94.2%

      \[\leadsto \frac{1 + \frac{0.3333333333333333 \cdot \frac{1}{N} + \color{blue}{-0.5}}{N}}{N} \]
    11. +-commutative94.2%

      \[\leadsto \frac{1 + \frac{\color{blue}{-0.5 + 0.3333333333333333 \cdot \frac{1}{N}}}{N}}{N} \]
    12. associate-*r/94.2%

      \[\leadsto \frac{1 + \frac{-0.5 + \color{blue}{\frac{0.3333333333333333 \cdot 1}{N}}}{N}}{N} \]
    13. metadata-eval94.2%

      \[\leadsto \frac{1 + \frac{-0.5 + \frac{\color{blue}{0.3333333333333333}}{N}}{N}}{N} \]
  5. Simplified94.2%

    \[\leadsto \color{blue}{\frac{1 + \frac{-0.5 + \frac{0.3333333333333333}{N}}{N}}{N}} \]
  6. Step-by-step derivation
    1. clear-num94.2%

      \[\leadsto \color{blue}{\frac{1}{\frac{N}{1 + \frac{-0.5 + \frac{0.3333333333333333}{N}}{N}}}} \]
    2. inv-pow94.2%

      \[\leadsto \color{blue}{{\left(\frac{N}{1 + \frac{-0.5 + \frac{0.3333333333333333}{N}}{N}}\right)}^{-1}} \]
  7. Applied egg-rr94.2%

    \[\leadsto \color{blue}{{\left(\frac{N}{1 + \frac{-0.5 + \frac{0.3333333333333333}{N}}{N}}\right)}^{-1}} \]
  8. Step-by-step derivation
    1. unpow-194.2%

      \[\leadsto \color{blue}{\frac{1}{\frac{N}{1 + \frac{-0.5 + \frac{0.3333333333333333}{N}}{N}}}} \]
    2. remove-double-neg94.2%

      \[\leadsto \frac{1}{\frac{N}{1 + \color{blue}{\left(-\left(-\frac{-0.5 + \frac{0.3333333333333333}{N}}{N}\right)\right)}}} \]
    3. neg-mul-194.2%

      \[\leadsto \frac{1}{\frac{N}{1 + \left(-\color{blue}{-1 \cdot \frac{-0.5 + \frac{0.3333333333333333}{N}}{N}}\right)}} \]
    4. associate-*r/94.2%

      \[\leadsto \frac{1}{\frac{N}{1 + \left(-\color{blue}{\frac{-1 \cdot \left(-0.5 + \frac{0.3333333333333333}{N}\right)}{N}}\right)}} \]
    5. neg-mul-194.2%

      \[\leadsto \frac{1}{\frac{N}{1 + \left(-\frac{\color{blue}{-\left(-0.5 + \frac{0.3333333333333333}{N}\right)}}{N}\right)}} \]
    6. distribute-neg-in94.2%

      \[\leadsto \frac{1}{\frac{N}{1 + \left(-\frac{\color{blue}{\left(--0.5\right) + \left(-\frac{0.3333333333333333}{N}\right)}}{N}\right)}} \]
    7. metadata-eval94.2%

      \[\leadsto \frac{1}{\frac{N}{1 + \left(-\frac{\color{blue}{0.5} + \left(-\frac{0.3333333333333333}{N}\right)}{N}\right)}} \]
    8. metadata-eval94.2%

      \[\leadsto \frac{1}{\frac{N}{1 + \left(-\frac{0.5 + \left(-\frac{\color{blue}{0.3333333333333333 \cdot 1}}{N}\right)}{N}\right)}} \]
    9. associate-*r/94.2%

      \[\leadsto \frac{1}{\frac{N}{1 + \left(-\frac{0.5 + \left(-\color{blue}{0.3333333333333333 \cdot \frac{1}{N}}\right)}{N}\right)}} \]
    10. sub-neg94.2%

      \[\leadsto \frac{1}{\frac{N}{1 + \left(-\frac{\color{blue}{0.5 - 0.3333333333333333 \cdot \frac{1}{N}}}{N}\right)}} \]
    11. associate-*r/94.2%

      \[\leadsto \frac{1}{\frac{N}{1 + \left(-\frac{0.5 - \color{blue}{\frac{0.3333333333333333 \cdot 1}{N}}}{N}\right)}} \]
    12. metadata-eval94.2%

      \[\leadsto \frac{1}{\frac{N}{1 + \left(-\frac{0.5 - \frac{\color{blue}{0.3333333333333333}}{N}}{N}\right)}} \]
    13. unsub-neg94.2%

      \[\leadsto \frac{1}{\frac{N}{1 + \left(-\frac{\color{blue}{0.5 + \left(-\frac{0.3333333333333333}{N}\right)}}{N}\right)}} \]
    14. unsub-neg94.2%

      \[\leadsto \frac{1}{\frac{N}{\color{blue}{1 - \frac{0.5 + \left(-\frac{0.3333333333333333}{N}\right)}{N}}}} \]
    15. unsub-neg94.2%

      \[\leadsto \frac{1}{\frac{N}{1 - \frac{\color{blue}{0.5 - \frac{0.3333333333333333}{N}}}{N}}} \]
  9. Simplified94.2%

    \[\leadsto \color{blue}{\frac{1}{\frac{N}{1 - \frac{0.5 + \frac{-0.3333333333333333}{N}}{N}}}} \]
  10. Taylor expanded in N around inf 94.7%

    \[\leadsto \frac{1}{\color{blue}{N \cdot \left(\left(1 + 0.5 \cdot \frac{1}{N}\right) - \frac{0.08333333333333333}{{N}^{2}}\right)}} \]
  11. Step-by-step derivation
    1. associate--l+94.7%

      \[\leadsto \frac{1}{N \cdot \color{blue}{\left(1 + \left(0.5 \cdot \frac{1}{N} - \frac{0.08333333333333333}{{N}^{2}}\right)\right)}} \]
    2. associate-*r/94.7%

      \[\leadsto \frac{1}{N \cdot \left(1 + \left(\color{blue}{\frac{0.5 \cdot 1}{N}} - \frac{0.08333333333333333}{{N}^{2}}\right)\right)} \]
    3. metadata-eval94.7%

      \[\leadsto \frac{1}{N \cdot \left(1 + \left(\frac{\color{blue}{0.5}}{N} - \frac{0.08333333333333333}{{N}^{2}}\right)\right)} \]
    4. unpow294.7%

      \[\leadsto \frac{1}{N \cdot \left(1 + \left(\frac{0.5}{N} - \frac{0.08333333333333333}{\color{blue}{N \cdot N}}\right)\right)} \]
    5. associate-/r*94.7%

      \[\leadsto \frac{1}{N \cdot \left(1 + \left(\frac{0.5}{N} - \color{blue}{\frac{\frac{0.08333333333333333}{N}}{N}}\right)\right)} \]
    6. metadata-eval94.7%

      \[\leadsto \frac{1}{N \cdot \left(1 + \left(\frac{0.5}{N} - \frac{\frac{\color{blue}{0.08333333333333333 \cdot 1}}{N}}{N}\right)\right)} \]
    7. associate-*r/94.7%

      \[\leadsto \frac{1}{N \cdot \left(1 + \left(\frac{0.5}{N} - \frac{\color{blue}{0.08333333333333333 \cdot \frac{1}{N}}}{N}\right)\right)} \]
    8. div-sub94.7%

      \[\leadsto \frac{1}{N \cdot \left(1 + \color{blue}{\frac{0.5 - 0.08333333333333333 \cdot \frac{1}{N}}{N}}\right)} \]
    9. cancel-sign-sub-inv94.7%

      \[\leadsto \frac{1}{N \cdot \left(1 + \frac{\color{blue}{0.5 + \left(-0.08333333333333333\right) \cdot \frac{1}{N}}}{N}\right)} \]
    10. associate-*r/94.7%

      \[\leadsto \frac{1}{N \cdot \left(1 + \frac{0.5 + \color{blue}{\frac{\left(-0.08333333333333333\right) \cdot 1}{N}}}{N}\right)} \]
    11. metadata-eval94.7%

      \[\leadsto \frac{1}{N \cdot \left(1 + \frac{0.5 + \frac{\color{blue}{-0.08333333333333333} \cdot 1}{N}}{N}\right)} \]
    12. metadata-eval94.7%

      \[\leadsto \frac{1}{N \cdot \left(1 + \frac{0.5 + \frac{\color{blue}{-0.08333333333333333}}{N}}{N}\right)} \]
  12. Simplified94.7%

    \[\leadsto \frac{1}{\color{blue}{N \cdot \left(1 + \frac{0.5 + \frac{-0.08333333333333333}{N}}{N}\right)}} \]
  13. Final simplification94.7%

    \[\leadsto \frac{-1}{N \cdot \left(-1 - \frac{0.5 + \frac{-0.08333333333333333}{N}}{N}\right)} \]
  14. Add Preprocessing

Alternative 6: 95.3% accurate, 18.6× speedup?

\[\begin{array}{l} \\ \frac{-1}{\frac{0.08333333333333333 - N \cdot \left(N + 0.5\right)}{N}} \end{array} \]
(FPCore (N)
 :precision binary64
 (/ -1.0 (/ (- 0.08333333333333333 (* N (+ N 0.5))) N)))
double code(double N) {
	return -1.0 / ((0.08333333333333333 - (N * (N + 0.5))) / N);
}
real(8) function code(n)
    real(8), intent (in) :: n
    code = (-1.0d0) / ((0.08333333333333333d0 - (n * (n + 0.5d0))) / n)
end function
public static double code(double N) {
	return -1.0 / ((0.08333333333333333 - (N * (N + 0.5))) / N);
}
def code(N):
	return -1.0 / ((0.08333333333333333 - (N * (N + 0.5))) / N)
function code(N)
	return Float64(-1.0 / Float64(Float64(0.08333333333333333 - Float64(N * Float64(N + 0.5))) / N))
end
function tmp = code(N)
	tmp = -1.0 / ((0.08333333333333333 - (N * (N + 0.5))) / N);
end
code[N_] := N[(-1.0 / N[(N[(0.08333333333333333 - N[(N * N[(N + 0.5), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / N), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{-1}{\frac{0.08333333333333333 - N \cdot \left(N + 0.5\right)}{N}}
\end{array}
Derivation
  1. Initial program 26.4%

    \[\log \left(N + 1\right) - \log N \]
  2. Add Preprocessing
  3. Taylor expanded in N around inf 94.2%

    \[\leadsto \color{blue}{\frac{\left(1 + \frac{0.3333333333333333}{{N}^{2}}\right) - 0.5 \cdot \frac{1}{N}}{N}} \]
  4. Step-by-step derivation
    1. associate--l+94.2%

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

      \[\leadsto \frac{1 + \left(\frac{0.3333333333333333}{\color{blue}{N \cdot N}} - 0.5 \cdot \frac{1}{N}\right)}{N} \]
    3. associate-/r*94.2%

      \[\leadsto \frac{1 + \left(\color{blue}{\frac{\frac{0.3333333333333333}{N}}{N}} - 0.5 \cdot \frac{1}{N}\right)}{N} \]
    4. metadata-eval94.2%

      \[\leadsto \frac{1 + \left(\frac{\frac{\color{blue}{0.3333333333333333 \cdot 1}}{N}}{N} - 0.5 \cdot \frac{1}{N}\right)}{N} \]
    5. associate-*r/94.2%

      \[\leadsto \frac{1 + \left(\frac{\color{blue}{0.3333333333333333 \cdot \frac{1}{N}}}{N} - 0.5 \cdot \frac{1}{N}\right)}{N} \]
    6. associate-*r/94.2%

      \[\leadsto \frac{1 + \left(\frac{0.3333333333333333 \cdot \frac{1}{N}}{N} - \color{blue}{\frac{0.5 \cdot 1}{N}}\right)}{N} \]
    7. metadata-eval94.2%

      \[\leadsto \frac{1 + \left(\frac{0.3333333333333333 \cdot \frac{1}{N}}{N} - \frac{\color{blue}{0.5}}{N}\right)}{N} \]
    8. div-sub94.2%

      \[\leadsto \frac{1 + \color{blue}{\frac{0.3333333333333333 \cdot \frac{1}{N} - 0.5}{N}}}{N} \]
    9. sub-neg94.2%

      \[\leadsto \frac{1 + \frac{\color{blue}{0.3333333333333333 \cdot \frac{1}{N} + \left(-0.5\right)}}{N}}{N} \]
    10. metadata-eval94.2%

      \[\leadsto \frac{1 + \frac{0.3333333333333333 \cdot \frac{1}{N} + \color{blue}{-0.5}}{N}}{N} \]
    11. +-commutative94.2%

      \[\leadsto \frac{1 + \frac{\color{blue}{-0.5 + 0.3333333333333333 \cdot \frac{1}{N}}}{N}}{N} \]
    12. associate-*r/94.2%

      \[\leadsto \frac{1 + \frac{-0.5 + \color{blue}{\frac{0.3333333333333333 \cdot 1}{N}}}{N}}{N} \]
    13. metadata-eval94.2%

      \[\leadsto \frac{1 + \frac{-0.5 + \frac{\color{blue}{0.3333333333333333}}{N}}{N}}{N} \]
  5. Simplified94.2%

    \[\leadsto \color{blue}{\frac{1 + \frac{-0.5 + \frac{0.3333333333333333}{N}}{N}}{N}} \]
  6. Step-by-step derivation
    1. clear-num94.2%

      \[\leadsto \color{blue}{\frac{1}{\frac{N}{1 + \frac{-0.5 + \frac{0.3333333333333333}{N}}{N}}}} \]
    2. inv-pow94.2%

      \[\leadsto \color{blue}{{\left(\frac{N}{1 + \frac{-0.5 + \frac{0.3333333333333333}{N}}{N}}\right)}^{-1}} \]
  7. Applied egg-rr94.2%

    \[\leadsto \color{blue}{{\left(\frac{N}{1 + \frac{-0.5 + \frac{0.3333333333333333}{N}}{N}}\right)}^{-1}} \]
  8. Step-by-step derivation
    1. unpow-194.2%

      \[\leadsto \color{blue}{\frac{1}{\frac{N}{1 + \frac{-0.5 + \frac{0.3333333333333333}{N}}{N}}}} \]
    2. remove-double-neg94.2%

      \[\leadsto \frac{1}{\frac{N}{1 + \color{blue}{\left(-\left(-\frac{-0.5 + \frac{0.3333333333333333}{N}}{N}\right)\right)}}} \]
    3. neg-mul-194.2%

      \[\leadsto \frac{1}{\frac{N}{1 + \left(-\color{blue}{-1 \cdot \frac{-0.5 + \frac{0.3333333333333333}{N}}{N}}\right)}} \]
    4. associate-*r/94.2%

      \[\leadsto \frac{1}{\frac{N}{1 + \left(-\color{blue}{\frac{-1 \cdot \left(-0.5 + \frac{0.3333333333333333}{N}\right)}{N}}\right)}} \]
    5. neg-mul-194.2%

      \[\leadsto \frac{1}{\frac{N}{1 + \left(-\frac{\color{blue}{-\left(-0.5 + \frac{0.3333333333333333}{N}\right)}}{N}\right)}} \]
    6. distribute-neg-in94.2%

      \[\leadsto \frac{1}{\frac{N}{1 + \left(-\frac{\color{blue}{\left(--0.5\right) + \left(-\frac{0.3333333333333333}{N}\right)}}{N}\right)}} \]
    7. metadata-eval94.2%

      \[\leadsto \frac{1}{\frac{N}{1 + \left(-\frac{\color{blue}{0.5} + \left(-\frac{0.3333333333333333}{N}\right)}{N}\right)}} \]
    8. metadata-eval94.2%

      \[\leadsto \frac{1}{\frac{N}{1 + \left(-\frac{0.5 + \left(-\frac{\color{blue}{0.3333333333333333 \cdot 1}}{N}\right)}{N}\right)}} \]
    9. associate-*r/94.2%

      \[\leadsto \frac{1}{\frac{N}{1 + \left(-\frac{0.5 + \left(-\color{blue}{0.3333333333333333 \cdot \frac{1}{N}}\right)}{N}\right)}} \]
    10. sub-neg94.2%

      \[\leadsto \frac{1}{\frac{N}{1 + \left(-\frac{\color{blue}{0.5 - 0.3333333333333333 \cdot \frac{1}{N}}}{N}\right)}} \]
    11. associate-*r/94.2%

      \[\leadsto \frac{1}{\frac{N}{1 + \left(-\frac{0.5 - \color{blue}{\frac{0.3333333333333333 \cdot 1}{N}}}{N}\right)}} \]
    12. metadata-eval94.2%

      \[\leadsto \frac{1}{\frac{N}{1 + \left(-\frac{0.5 - \frac{\color{blue}{0.3333333333333333}}{N}}{N}\right)}} \]
    13. unsub-neg94.2%

      \[\leadsto \frac{1}{\frac{N}{1 + \left(-\frac{\color{blue}{0.5 + \left(-\frac{0.3333333333333333}{N}\right)}}{N}\right)}} \]
    14. unsub-neg94.2%

      \[\leadsto \frac{1}{\frac{N}{\color{blue}{1 - \frac{0.5 + \left(-\frac{0.3333333333333333}{N}\right)}{N}}}} \]
    15. unsub-neg94.2%

      \[\leadsto \frac{1}{\frac{N}{1 - \frac{\color{blue}{0.5 - \frac{0.3333333333333333}{N}}}{N}}} \]
  9. Simplified94.2%

    \[\leadsto \color{blue}{\frac{1}{\frac{N}{1 - \frac{0.5 + \frac{-0.3333333333333333}{N}}{N}}}} \]
  10. Taylor expanded in N around inf 94.7%

    \[\leadsto \frac{1}{\color{blue}{N \cdot \left(\left(1 + 0.5 \cdot \frac{1}{N}\right) - \frac{0.08333333333333333}{{N}^{2}}\right)}} \]
  11. Step-by-step derivation
    1. associate--l+94.7%

      \[\leadsto \frac{1}{N \cdot \color{blue}{\left(1 + \left(0.5 \cdot \frac{1}{N} - \frac{0.08333333333333333}{{N}^{2}}\right)\right)}} \]
    2. associate-*r/94.7%

      \[\leadsto \frac{1}{N \cdot \left(1 + \left(\color{blue}{\frac{0.5 \cdot 1}{N}} - \frac{0.08333333333333333}{{N}^{2}}\right)\right)} \]
    3. metadata-eval94.7%

      \[\leadsto \frac{1}{N \cdot \left(1 + \left(\frac{\color{blue}{0.5}}{N} - \frac{0.08333333333333333}{{N}^{2}}\right)\right)} \]
    4. unpow294.7%

      \[\leadsto \frac{1}{N \cdot \left(1 + \left(\frac{0.5}{N} - \frac{0.08333333333333333}{\color{blue}{N \cdot N}}\right)\right)} \]
    5. associate-/r*94.7%

      \[\leadsto \frac{1}{N \cdot \left(1 + \left(\frac{0.5}{N} - \color{blue}{\frac{\frac{0.08333333333333333}{N}}{N}}\right)\right)} \]
    6. metadata-eval94.7%

      \[\leadsto \frac{1}{N \cdot \left(1 + \left(\frac{0.5}{N} - \frac{\frac{\color{blue}{0.08333333333333333 \cdot 1}}{N}}{N}\right)\right)} \]
    7. associate-*r/94.7%

      \[\leadsto \frac{1}{N \cdot \left(1 + \left(\frac{0.5}{N} - \frac{\color{blue}{0.08333333333333333 \cdot \frac{1}{N}}}{N}\right)\right)} \]
    8. div-sub94.7%

      \[\leadsto \frac{1}{N \cdot \left(1 + \color{blue}{\frac{0.5 - 0.08333333333333333 \cdot \frac{1}{N}}{N}}\right)} \]
    9. cancel-sign-sub-inv94.7%

      \[\leadsto \frac{1}{N \cdot \left(1 + \frac{\color{blue}{0.5 + \left(-0.08333333333333333\right) \cdot \frac{1}{N}}}{N}\right)} \]
    10. associate-*r/94.7%

      \[\leadsto \frac{1}{N \cdot \left(1 + \frac{0.5 + \color{blue}{\frac{\left(-0.08333333333333333\right) \cdot 1}{N}}}{N}\right)} \]
    11. metadata-eval94.7%

      \[\leadsto \frac{1}{N \cdot \left(1 + \frac{0.5 + \frac{\color{blue}{-0.08333333333333333} \cdot 1}{N}}{N}\right)} \]
    12. metadata-eval94.7%

      \[\leadsto \frac{1}{N \cdot \left(1 + \frac{0.5 + \frac{\color{blue}{-0.08333333333333333}}{N}}{N}\right)} \]
  12. Simplified94.7%

    \[\leadsto \frac{1}{\color{blue}{N \cdot \left(1 + \frac{0.5 + \frac{-0.08333333333333333}{N}}{N}\right)}} \]
  13. Taylor expanded in N around 0 94.7%

    \[\leadsto \frac{1}{\color{blue}{\frac{N \cdot \left(0.5 + N\right) - 0.08333333333333333}{N}}} \]
  14. Final simplification94.7%

    \[\leadsto \frac{-1}{\frac{0.08333333333333333 - N \cdot \left(N + 0.5\right)}{N}} \]
  15. Add Preprocessing

Alternative 7: 92.8% accurate, 41.0× speedup?

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

\\
\frac{1}{N + 0.5}
\end{array}
Derivation
  1. Initial program 26.4%

    \[\log \left(N + 1\right) - \log N \]
  2. Add Preprocessing
  3. Taylor expanded in N around inf 94.2%

    \[\leadsto \color{blue}{\frac{\left(1 + \frac{0.3333333333333333}{{N}^{2}}\right) - 0.5 \cdot \frac{1}{N}}{N}} \]
  4. Step-by-step derivation
    1. associate--l+94.2%

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

      \[\leadsto \frac{1 + \left(\frac{0.3333333333333333}{\color{blue}{N \cdot N}} - 0.5 \cdot \frac{1}{N}\right)}{N} \]
    3. associate-/r*94.2%

      \[\leadsto \frac{1 + \left(\color{blue}{\frac{\frac{0.3333333333333333}{N}}{N}} - 0.5 \cdot \frac{1}{N}\right)}{N} \]
    4. metadata-eval94.2%

      \[\leadsto \frac{1 + \left(\frac{\frac{\color{blue}{0.3333333333333333 \cdot 1}}{N}}{N} - 0.5 \cdot \frac{1}{N}\right)}{N} \]
    5. associate-*r/94.2%

      \[\leadsto \frac{1 + \left(\frac{\color{blue}{0.3333333333333333 \cdot \frac{1}{N}}}{N} - 0.5 \cdot \frac{1}{N}\right)}{N} \]
    6. associate-*r/94.2%

      \[\leadsto \frac{1 + \left(\frac{0.3333333333333333 \cdot \frac{1}{N}}{N} - \color{blue}{\frac{0.5 \cdot 1}{N}}\right)}{N} \]
    7. metadata-eval94.2%

      \[\leadsto \frac{1 + \left(\frac{0.3333333333333333 \cdot \frac{1}{N}}{N} - \frac{\color{blue}{0.5}}{N}\right)}{N} \]
    8. div-sub94.2%

      \[\leadsto \frac{1 + \color{blue}{\frac{0.3333333333333333 \cdot \frac{1}{N} - 0.5}{N}}}{N} \]
    9. sub-neg94.2%

      \[\leadsto \frac{1 + \frac{\color{blue}{0.3333333333333333 \cdot \frac{1}{N} + \left(-0.5\right)}}{N}}{N} \]
    10. metadata-eval94.2%

      \[\leadsto \frac{1 + \frac{0.3333333333333333 \cdot \frac{1}{N} + \color{blue}{-0.5}}{N}}{N} \]
    11. +-commutative94.2%

      \[\leadsto \frac{1 + \frac{\color{blue}{-0.5 + 0.3333333333333333 \cdot \frac{1}{N}}}{N}}{N} \]
    12. associate-*r/94.2%

      \[\leadsto \frac{1 + \frac{-0.5 + \color{blue}{\frac{0.3333333333333333 \cdot 1}{N}}}{N}}{N} \]
    13. metadata-eval94.2%

      \[\leadsto \frac{1 + \frac{-0.5 + \frac{\color{blue}{0.3333333333333333}}{N}}{N}}{N} \]
  5. Simplified94.2%

    \[\leadsto \color{blue}{\frac{1 + \frac{-0.5 + \frac{0.3333333333333333}{N}}{N}}{N}} \]
  6. Step-by-step derivation
    1. clear-num94.2%

      \[\leadsto \color{blue}{\frac{1}{\frac{N}{1 + \frac{-0.5 + \frac{0.3333333333333333}{N}}{N}}}} \]
    2. inv-pow94.2%

      \[\leadsto \color{blue}{{\left(\frac{N}{1 + \frac{-0.5 + \frac{0.3333333333333333}{N}}{N}}\right)}^{-1}} \]
  7. Applied egg-rr94.2%

    \[\leadsto \color{blue}{{\left(\frac{N}{1 + \frac{-0.5 + \frac{0.3333333333333333}{N}}{N}}\right)}^{-1}} \]
  8. Step-by-step derivation
    1. unpow-194.2%

      \[\leadsto \color{blue}{\frac{1}{\frac{N}{1 + \frac{-0.5 + \frac{0.3333333333333333}{N}}{N}}}} \]
    2. remove-double-neg94.2%

      \[\leadsto \frac{1}{\frac{N}{1 + \color{blue}{\left(-\left(-\frac{-0.5 + \frac{0.3333333333333333}{N}}{N}\right)\right)}}} \]
    3. neg-mul-194.2%

      \[\leadsto \frac{1}{\frac{N}{1 + \left(-\color{blue}{-1 \cdot \frac{-0.5 + \frac{0.3333333333333333}{N}}{N}}\right)}} \]
    4. associate-*r/94.2%

      \[\leadsto \frac{1}{\frac{N}{1 + \left(-\color{blue}{\frac{-1 \cdot \left(-0.5 + \frac{0.3333333333333333}{N}\right)}{N}}\right)}} \]
    5. neg-mul-194.2%

      \[\leadsto \frac{1}{\frac{N}{1 + \left(-\frac{\color{blue}{-\left(-0.5 + \frac{0.3333333333333333}{N}\right)}}{N}\right)}} \]
    6. distribute-neg-in94.2%

      \[\leadsto \frac{1}{\frac{N}{1 + \left(-\frac{\color{blue}{\left(--0.5\right) + \left(-\frac{0.3333333333333333}{N}\right)}}{N}\right)}} \]
    7. metadata-eval94.2%

      \[\leadsto \frac{1}{\frac{N}{1 + \left(-\frac{\color{blue}{0.5} + \left(-\frac{0.3333333333333333}{N}\right)}{N}\right)}} \]
    8. metadata-eval94.2%

      \[\leadsto \frac{1}{\frac{N}{1 + \left(-\frac{0.5 + \left(-\frac{\color{blue}{0.3333333333333333 \cdot 1}}{N}\right)}{N}\right)}} \]
    9. associate-*r/94.2%

      \[\leadsto \frac{1}{\frac{N}{1 + \left(-\frac{0.5 + \left(-\color{blue}{0.3333333333333333 \cdot \frac{1}{N}}\right)}{N}\right)}} \]
    10. sub-neg94.2%

      \[\leadsto \frac{1}{\frac{N}{1 + \left(-\frac{\color{blue}{0.5 - 0.3333333333333333 \cdot \frac{1}{N}}}{N}\right)}} \]
    11. associate-*r/94.2%

      \[\leadsto \frac{1}{\frac{N}{1 + \left(-\frac{0.5 - \color{blue}{\frac{0.3333333333333333 \cdot 1}{N}}}{N}\right)}} \]
    12. metadata-eval94.2%

      \[\leadsto \frac{1}{\frac{N}{1 + \left(-\frac{0.5 - \frac{\color{blue}{0.3333333333333333}}{N}}{N}\right)}} \]
    13. unsub-neg94.2%

      \[\leadsto \frac{1}{\frac{N}{1 + \left(-\frac{\color{blue}{0.5 + \left(-\frac{0.3333333333333333}{N}\right)}}{N}\right)}} \]
    14. unsub-neg94.2%

      \[\leadsto \frac{1}{\frac{N}{\color{blue}{1 - \frac{0.5 + \left(-\frac{0.3333333333333333}{N}\right)}{N}}}} \]
    15. unsub-neg94.2%

      \[\leadsto \frac{1}{\frac{N}{1 - \frac{\color{blue}{0.5 - \frac{0.3333333333333333}{N}}}{N}}} \]
  9. Simplified94.2%

    \[\leadsto \color{blue}{\frac{1}{\frac{N}{1 - \frac{0.5 + \frac{-0.3333333333333333}{N}}{N}}}} \]
  10. Taylor expanded in N around inf 91.7%

    \[\leadsto \frac{1}{\color{blue}{N \cdot \left(1 + 0.5 \cdot \frac{1}{N}\right)}} \]
  11. Step-by-step derivation
    1. distribute-rgt-in91.8%

      \[\leadsto \frac{1}{\color{blue}{1 \cdot N + \left(0.5 \cdot \frac{1}{N}\right) \cdot N}} \]
    2. *-lft-identity91.8%

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

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

      \[\leadsto \frac{1}{N + 0.5 \cdot \left(\color{blue}{{N}^{-1}} \cdot N\right)} \]
    5. pow-plus91.8%

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

      \[\leadsto \frac{1}{N + 0.5 \cdot {N}^{\color{blue}{0}}} \]
    7. metadata-eval91.8%

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

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

    \[\leadsto \frac{1}{\color{blue}{N + 0.5}} \]
  13. Add Preprocessing

Alternative 8: 84.2% 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 26.4%

    \[\log \left(N + 1\right) - \log N \]
  2. Add Preprocessing
  3. Taylor expanded in N around inf 82.4%

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

Alternative 9: 9.9% accurate, 205.0× speedup?

\[\begin{array}{l} \\ 2 \end{array} \]
(FPCore (N) :precision binary64 2.0)
double code(double N) {
	return 2.0;
}
real(8) function code(n)
    real(8), intent (in) :: n
    code = 2.0d0
end function
public static double code(double N) {
	return 2.0;
}
def code(N):
	return 2.0
function code(N)
	return 2.0
end
function tmp = code(N)
	tmp = 2.0;
end
code[N_] := 2.0
\begin{array}{l}

\\
2
\end{array}
Derivation
  1. Initial program 26.4%

    \[\log \left(N + 1\right) - \log N \]
  2. Add Preprocessing
  3. Taylor expanded in N around inf 94.2%

    \[\leadsto \color{blue}{\frac{\left(1 + \frac{0.3333333333333333}{{N}^{2}}\right) - 0.5 \cdot \frac{1}{N}}{N}} \]
  4. Step-by-step derivation
    1. associate--l+94.2%

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

      \[\leadsto \frac{1 + \left(\frac{0.3333333333333333}{\color{blue}{N \cdot N}} - 0.5 \cdot \frac{1}{N}\right)}{N} \]
    3. associate-/r*94.2%

      \[\leadsto \frac{1 + \left(\color{blue}{\frac{\frac{0.3333333333333333}{N}}{N}} - 0.5 \cdot \frac{1}{N}\right)}{N} \]
    4. metadata-eval94.2%

      \[\leadsto \frac{1 + \left(\frac{\frac{\color{blue}{0.3333333333333333 \cdot 1}}{N}}{N} - 0.5 \cdot \frac{1}{N}\right)}{N} \]
    5. associate-*r/94.2%

      \[\leadsto \frac{1 + \left(\frac{\color{blue}{0.3333333333333333 \cdot \frac{1}{N}}}{N} - 0.5 \cdot \frac{1}{N}\right)}{N} \]
    6. associate-*r/94.2%

      \[\leadsto \frac{1 + \left(\frac{0.3333333333333333 \cdot \frac{1}{N}}{N} - \color{blue}{\frac{0.5 \cdot 1}{N}}\right)}{N} \]
    7. metadata-eval94.2%

      \[\leadsto \frac{1 + \left(\frac{0.3333333333333333 \cdot \frac{1}{N}}{N} - \frac{\color{blue}{0.5}}{N}\right)}{N} \]
    8. div-sub94.2%

      \[\leadsto \frac{1 + \color{blue}{\frac{0.3333333333333333 \cdot \frac{1}{N} - 0.5}{N}}}{N} \]
    9. sub-neg94.2%

      \[\leadsto \frac{1 + \frac{\color{blue}{0.3333333333333333 \cdot \frac{1}{N} + \left(-0.5\right)}}{N}}{N} \]
    10. metadata-eval94.2%

      \[\leadsto \frac{1 + \frac{0.3333333333333333 \cdot \frac{1}{N} + \color{blue}{-0.5}}{N}}{N} \]
    11. +-commutative94.2%

      \[\leadsto \frac{1 + \frac{\color{blue}{-0.5 + 0.3333333333333333 \cdot \frac{1}{N}}}{N}}{N} \]
    12. associate-*r/94.2%

      \[\leadsto \frac{1 + \frac{-0.5 + \color{blue}{\frac{0.3333333333333333 \cdot 1}{N}}}{N}}{N} \]
    13. metadata-eval94.2%

      \[\leadsto \frac{1 + \frac{-0.5 + \frac{\color{blue}{0.3333333333333333}}{N}}{N}}{N} \]
  5. Simplified94.2%

    \[\leadsto \color{blue}{\frac{1 + \frac{-0.5 + \frac{0.3333333333333333}{N}}{N}}{N}} \]
  6. Step-by-step derivation
    1. clear-num94.2%

      \[\leadsto \color{blue}{\frac{1}{\frac{N}{1 + \frac{-0.5 + \frac{0.3333333333333333}{N}}{N}}}} \]
    2. inv-pow94.2%

      \[\leadsto \color{blue}{{\left(\frac{N}{1 + \frac{-0.5 + \frac{0.3333333333333333}{N}}{N}}\right)}^{-1}} \]
  7. Applied egg-rr94.2%

    \[\leadsto \color{blue}{{\left(\frac{N}{1 + \frac{-0.5 + \frac{0.3333333333333333}{N}}{N}}\right)}^{-1}} \]
  8. Step-by-step derivation
    1. unpow-194.2%

      \[\leadsto \color{blue}{\frac{1}{\frac{N}{1 + \frac{-0.5 + \frac{0.3333333333333333}{N}}{N}}}} \]
    2. remove-double-neg94.2%

      \[\leadsto \frac{1}{\frac{N}{1 + \color{blue}{\left(-\left(-\frac{-0.5 + \frac{0.3333333333333333}{N}}{N}\right)\right)}}} \]
    3. neg-mul-194.2%

      \[\leadsto \frac{1}{\frac{N}{1 + \left(-\color{blue}{-1 \cdot \frac{-0.5 + \frac{0.3333333333333333}{N}}{N}}\right)}} \]
    4. associate-*r/94.2%

      \[\leadsto \frac{1}{\frac{N}{1 + \left(-\color{blue}{\frac{-1 \cdot \left(-0.5 + \frac{0.3333333333333333}{N}\right)}{N}}\right)}} \]
    5. neg-mul-194.2%

      \[\leadsto \frac{1}{\frac{N}{1 + \left(-\frac{\color{blue}{-\left(-0.5 + \frac{0.3333333333333333}{N}\right)}}{N}\right)}} \]
    6. distribute-neg-in94.2%

      \[\leadsto \frac{1}{\frac{N}{1 + \left(-\frac{\color{blue}{\left(--0.5\right) + \left(-\frac{0.3333333333333333}{N}\right)}}{N}\right)}} \]
    7. metadata-eval94.2%

      \[\leadsto \frac{1}{\frac{N}{1 + \left(-\frac{\color{blue}{0.5} + \left(-\frac{0.3333333333333333}{N}\right)}{N}\right)}} \]
    8. metadata-eval94.2%

      \[\leadsto \frac{1}{\frac{N}{1 + \left(-\frac{0.5 + \left(-\frac{\color{blue}{0.3333333333333333 \cdot 1}}{N}\right)}{N}\right)}} \]
    9. associate-*r/94.2%

      \[\leadsto \frac{1}{\frac{N}{1 + \left(-\frac{0.5 + \left(-\color{blue}{0.3333333333333333 \cdot \frac{1}{N}}\right)}{N}\right)}} \]
    10. sub-neg94.2%

      \[\leadsto \frac{1}{\frac{N}{1 + \left(-\frac{\color{blue}{0.5 - 0.3333333333333333 \cdot \frac{1}{N}}}{N}\right)}} \]
    11. associate-*r/94.2%

      \[\leadsto \frac{1}{\frac{N}{1 + \left(-\frac{0.5 - \color{blue}{\frac{0.3333333333333333 \cdot 1}{N}}}{N}\right)}} \]
    12. metadata-eval94.2%

      \[\leadsto \frac{1}{\frac{N}{1 + \left(-\frac{0.5 - \frac{\color{blue}{0.3333333333333333}}{N}}{N}\right)}} \]
    13. unsub-neg94.2%

      \[\leadsto \frac{1}{\frac{N}{1 + \left(-\frac{\color{blue}{0.5 + \left(-\frac{0.3333333333333333}{N}\right)}}{N}\right)}} \]
    14. unsub-neg94.2%

      \[\leadsto \frac{1}{\frac{N}{\color{blue}{1 - \frac{0.5 + \left(-\frac{0.3333333333333333}{N}\right)}{N}}}} \]
    15. unsub-neg94.2%

      \[\leadsto \frac{1}{\frac{N}{1 - \frac{\color{blue}{0.5 - \frac{0.3333333333333333}{N}}}{N}}} \]
  9. Simplified94.2%

    \[\leadsto \color{blue}{\frac{1}{\frac{N}{1 - \frac{0.5 + \frac{-0.3333333333333333}{N}}{N}}}} \]
  10. Taylor expanded in N around inf 91.7%

    \[\leadsto \frac{1}{\color{blue}{N \cdot \left(1 + 0.5 \cdot \frac{1}{N}\right)}} \]
  11. Step-by-step derivation
    1. distribute-rgt-in91.8%

      \[\leadsto \frac{1}{\color{blue}{1 \cdot N + \left(0.5 \cdot \frac{1}{N}\right) \cdot N}} \]
    2. *-lft-identity91.8%

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

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

      \[\leadsto \frac{1}{N + 0.5 \cdot \left(\color{blue}{{N}^{-1}} \cdot N\right)} \]
    5. pow-plus91.8%

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

      \[\leadsto \frac{1}{N + 0.5 \cdot {N}^{\color{blue}{0}}} \]
    7. metadata-eval91.8%

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

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

    \[\leadsto \frac{1}{\color{blue}{N + 0.5}} \]
  13. Taylor expanded in N around 0 10.0%

    \[\leadsto \color{blue}{2} \]
  14. Add Preprocessing

Developer Target 1: 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 2024129 
(FPCore (N)
  :name "2log (problem 3.3.6)"
  :precision binary64
  :pre (and (> N 1.0) (< N 1e+40))

  :alt
  (! :herbie-platform default (log1p (/ 1 N)))

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