Hi,
Im trying to prove that a prime $p\neq 3$ is of the form $p=x^2 + 3y^2$ if $p \equiv 1 \pmod{3}$.
I have think in a prove as follows:
As we know that $-3$ is a quadratic residue mod p, we know that the ideal $(p)$ must divide $(x^2 + 3) = (x + \sqrt{-3})(x - \sqrt{-3})$ in the ring...