> See

It was apparently harder than I thought.

> http://www.mathmeth.com/tom/files/pyth.pdf

> which claims a proof by infinite descent that

> x^2+y^2 and x^2-y^2 cannot both be odd squares.

>

> David (who miserably failed to find a simpler proof)

I didn't have a proof but guessed it would be relatively easy when

there is a known parametrization of all Pythagorean triples.

I only did a brute force search to see there were no small solutions.

--

Jens Kruse Andersen