\log \left(N + 1\right) - \log N
\begin{array}{l}
\mathbf{if}\;N \le 7072.329313818584:\\
\;\;\;\;\log \left(\sqrt{1 + \frac{1}{N}}\right) + \log \left(\sqrt{1 + \frac{1}{N}}\right)\\
\mathbf{else}:\\
\;\;\;\;\frac{\frac{\frac{1}{3}}{N \cdot N}}{N} + \left(\frac{1}{N} + \frac{\frac{-1}{2}}{N \cdot N}\right)\\
\end{array}double f(double N) {
double r2085973 = N;
double r2085974 = 1.0;
double r2085975 = r2085973 + r2085974;
double r2085976 = log(r2085975);
double r2085977 = log(r2085973);
double r2085978 = r2085976 - r2085977;
return r2085978;
}
double f(double N) {
double r2085979 = N;
double r2085980 = 7072.329313818584;
bool r2085981 = r2085979 <= r2085980;
double r2085982 = 1.0;
double r2085983 = r2085982 / r2085979;
double r2085984 = r2085982 + r2085983;
double r2085985 = sqrt(r2085984);
double r2085986 = log(r2085985);
double r2085987 = r2085986 + r2085986;
double r2085988 = 0.3333333333333333;
double r2085989 = r2085979 * r2085979;
double r2085990 = r2085988 / r2085989;
double r2085991 = r2085990 / r2085979;
double r2085992 = -0.5;
double r2085993 = r2085992 / r2085989;
double r2085994 = r2085983 + r2085993;
double r2085995 = r2085991 + r2085994;
double r2085996 = r2085981 ? r2085987 : r2085995;
return r2085996;
}



Bits error versus N
Results
if N < 7072.329313818584Initial program 0.1
rmApplied diff-log0.1
Taylor expanded around -inf 0.1
rmApplied add-sqr-sqrt0.1
Applied log-prod0.1
if 7072.329313818584 < N Initial program 59.6
rmApplied diff-log59.3
Taylor expanded around inf 0.0
Simplified0.0
Final simplification0.1
herbie shell --seed 2019107
(FPCore (N)
:name "2log (problem 3.3.6)"
(- (log (+ N 1)) (log N)))