Legendre function is broken

[JASory]

a^p-1 = 1 mod p is a necessary but not sufficient condition for primality. This is resulting in an extremely high error rate.

[cmpute]

I intentionally didn't include the primality check in the legendre function, because this crate doesn't deal with anything with primality test. This is clearly stated in the documentation

[JASory]

I intentionally didn't include the primality check in the legendre function, because this crate doesn't deal with anything with primality test. This is clearly stated in the documentation

https://docs.rs/num-modular/0.5.1/num_modular/trait.ModularSymbols.html#tymethod.checked_legendre

[cmpute]

@JASory The doc says

Checked version of legendre(), return None if n is not prime

This doesn't mean that it will do a full primality check (you can check the implementation). But the doc definitely needs to be improved, thanks for pointing out and I will make this clear