Sum of two squares theorem
= Sum of two squares theorem
{wiki}
A positive integer is a sum of two integer squares exactly when every prime factor congruent to $3$ modulo $4$ has even exponent in its prime factorization.
= Sum of two squares theorem
{wiki}
A positive integer is a sum of two integer squares exactly when every prime factor congruent to $3$ modulo $4$ has even exponent in its prime factorization.