\log \left(N + 1\right) - \log N
\begin{array}{l}
\mathbf{if}\;\log \left(N + 1\right) - \log N \le 5.1047487659161561168730258941650390625 \cdot 10^{-7}:\\
\;\;\;\;\frac{\frac{\frac{0.3333333333333333148296162562473909929395}{{N}^{2}} \cdot \frac{0.3333333333333333148296162562473909929395}{{N}^{2}} - \left(1 - \frac{0.5}{N}\right) \cdot \left(1 - \frac{0.5}{N}\right)}{N}}{\frac{0.3333333333333333148296162562473909929395}{{N}^{2}} - \left(1 - \frac{0.5}{N}\right)}\\
\mathbf{else}:\\
\;\;\;\;\left(\log \left({N}^{3} + {1}^{3}\right) - \log \left(N \cdot N + \left(1 \cdot 1 - N \cdot 1\right)\right)\right) - \log N\\
\end{array}double f(double N) {
double r35420 = N;
double r35421 = 1.0;
double r35422 = r35420 + r35421;
double r35423 = log(r35422);
double r35424 = log(r35420);
double r35425 = r35423 - r35424;
return r35425;
}
double f(double N) {
double r35426 = N;
double r35427 = 1.0;
double r35428 = r35426 + r35427;
double r35429 = log(r35428);
double r35430 = log(r35426);
double r35431 = r35429 - r35430;
double r35432 = 5.104748765916156e-07;
bool r35433 = r35431 <= r35432;
double r35434 = 0.3333333333333333;
double r35435 = 2.0;
double r35436 = pow(r35426, r35435);
double r35437 = r35434 / r35436;
double r35438 = r35437 * r35437;
double r35439 = 0.5;
double r35440 = r35439 / r35426;
double r35441 = r35427 - r35440;
double r35442 = r35441 * r35441;
double r35443 = r35438 - r35442;
double r35444 = r35443 / r35426;
double r35445 = r35437 - r35441;
double r35446 = r35444 / r35445;
double r35447 = 3.0;
double r35448 = pow(r35426, r35447);
double r35449 = pow(r35427, r35447);
double r35450 = r35448 + r35449;
double r35451 = log(r35450);
double r35452 = r35426 * r35426;
double r35453 = r35427 * r35427;
double r35454 = r35426 * r35427;
double r35455 = r35453 - r35454;
double r35456 = r35452 + r35455;
double r35457 = log(r35456);
double r35458 = r35451 - r35457;
double r35459 = r35458 - r35430;
double r35460 = r35433 ? r35446 : r35459;
return r35460;
}



Bits error versus N
Results
if (- (log (+ N 1.0)) (log N)) < 5.104748765916156e-07Initial program 59.9
Taylor expanded around inf 0.0
Simplified0.0
rmApplied flip-+0.0
Applied associate-*r/0.0
Simplified0.0
if 5.104748765916156e-07 < (- (log (+ N 1.0)) (log N)) Initial program 0.3
rmApplied flip3-+0.3
Applied log-div0.3
Final simplification0.2
herbie shell --seed 2019294
(FPCore (N)
:name "2log (problem 3.3.6)"
:precision binary64
(- (log (+ N 1)) (log N)))