Classical reduction: $\gcd(N, a^{r/2} \mp 1)$ are nontrivial factors when $N \nmid a^{r/2}+1$

Initializing...

Classical reduction: $\gcd(N, a^{r/2} \mp 1)$ are nontrivial factors when $N \nmid a^{r/2}+1$ · Prove2Me