\log \left(N + 1\right) - \log N
\begin{array}{l}
\mathbf{if}\;N \le 6535.778532396666378190275281667709350586:\\
\;\;\;\;\log \left(\frac{\frac{N + 1}{\sqrt{N}}}{\sqrt{N}}\right)\\
\mathbf{else}:\\
\;\;\;\;\frac{0.3333333333333333148296162562473909929395}{{N}^{3}} + \frac{1 - \frac{0.5}{N}}{N}\\
\end{array}double f(double N) {
double r44516 = N;
double r44517 = 1.0;
double r44518 = r44516 + r44517;
double r44519 = log(r44518);
double r44520 = log(r44516);
double r44521 = r44519 - r44520;
return r44521;
}
double f(double N) {
double r44522 = N;
double r44523 = 6535.778532396666;
bool r44524 = r44522 <= r44523;
double r44525 = 1.0;
double r44526 = r44522 + r44525;
double r44527 = sqrt(r44522);
double r44528 = r44526 / r44527;
double r44529 = r44528 / r44527;
double r44530 = log(r44529);
double r44531 = 0.3333333333333333;
double r44532 = 3.0;
double r44533 = pow(r44522, r44532);
double r44534 = r44531 / r44533;
double r44535 = 0.5;
double r44536 = r44535 / r44522;
double r44537 = r44525 - r44536;
double r44538 = r44537 / r44522;
double r44539 = r44534 + r44538;
double r44540 = r44524 ? r44530 : r44539;
return r44540;
}



Bits error versus N
Results
if N < 6535.778532396666Initial program 0.1
rmApplied diff-log0.1
rmApplied add-sqr-sqrt0.1
Applied associate-/r*0.1
if 6535.778532396666 < N Initial program 59.4
Taylor expanded around inf 0.0
Simplified0.0
Final simplification0.1
herbie shell --seed 2019351
(FPCore (N)
:name "2log (problem 3.3.6)"
:precision binary64
(- (log (+ N 1)) (log N)))