\log \left(N + 1\right) - \log N
\begin{array}{l}
\mathbf{if}\;N \le 4122.92847833978430571733042597770690918:\\
\;\;\;\;\sqrt[3]{{\left(\log \left(N + 1\right)\right)}^{3}} - \log N\\
\mathbf{else}:\\
\;\;\;\;\frac{0.3333333333333333148296162562473909929395}{{N}^{3}} + \frac{1 - \frac{0.5}{N}}{N}\\
\end{array}double f(double N) {
double r53769 = N;
double r53770 = 1.0;
double r53771 = r53769 + r53770;
double r53772 = log(r53771);
double r53773 = log(r53769);
double r53774 = r53772 - r53773;
return r53774;
}
double f(double N) {
double r53775 = N;
double r53776 = 4122.928478339784;
bool r53777 = r53775 <= r53776;
double r53778 = 1.0;
double r53779 = r53775 + r53778;
double r53780 = log(r53779);
double r53781 = 3.0;
double r53782 = pow(r53780, r53781);
double r53783 = cbrt(r53782);
double r53784 = log(r53775);
double r53785 = r53783 - r53784;
double r53786 = 0.3333333333333333;
double r53787 = pow(r53775, r53781);
double r53788 = r53786 / r53787;
double r53789 = 0.5;
double r53790 = r53789 / r53775;
double r53791 = r53778 - r53790;
double r53792 = r53791 / r53775;
double r53793 = r53788 + r53792;
double r53794 = r53777 ? r53785 : r53793;
return r53794;
}



Bits error versus N
Results
if N < 4122.928478339784Initial program 0.1
rmApplied add-cbrt-cube0.1
Simplified0.1
if 4122.928478339784 < N Initial program 59.4
Taylor expanded around inf 0.0
Simplified0.0
Final simplification0.1
herbie shell --seed 2019325
(FPCore (N)
:name "2log (problem 3.3.6)"
:precision binary64
(- (log (+ N 1)) (log N)))