Pairing Pythagorean Pairs

Lorenz Halbeisen, Norbert Hungerbühler

A pair $(a,b)$ of positive integers is a pythagorean pair if $a^2+b^2=\square$ (i.e., $a^2+b^2$ is a square). A pythagorean pair $(a,b)$ is called a double-pythapotent pair if…