Pythagorean triple
= Pythagorean triple
{c}
{title2=$x^2+y^2=z^2$}
{wiki}
A Pythagorean triple consists of three positive <integers> satisfying $x^2+y^2=z^2$. It is primitive when their <greatest common divisor> is one. Reducing their <square numbers> modulo $3$ shows that at least one leg is divisible by $3$; reducing modulo $4$ shows that both legs cannot be odd.