# Is mpz_legendre defined for p=2?

**Kevin Ryde
**
user42@zip.com.au

*Mon, 24 Feb 2003 08:30:43 +1000*

"Andrew Friedley (CNS Student Support)" <saai@henon.cns.uni.edu> writes:
>*
*>* Looking at the information on mpz_legendre() in the manual, it claims
*>* that it is only defined for p being an odd positive prime.
*
True, that's the definition for the legendre symbol.
>* I have tried
*>* using mpz_legendre() with p=2 and it seems to work as expected, is this
*>* correct?
*
In the current implementation mpz_legendre, mpz_jacobi and
mpz_kronecker are all aliases for the one function (the kronecker
flavour).
So calling mpz_legendre with inputs outside its documented range
works, though of course if you really want an even denominator then
you should be calling mpz_kronecker, for which such things are
defined.