Pythagorean

> (take 10 (match-all nats (list integer) [<join _ (& <cons $x _> <join _ (& <cons $y _> <join _ <cons (& ?(lambda [$z] (eq? (* z z) (+ (* x x) (* y y)))) $z) _>>)>)> [x y z]]))
{[3 4 5] [6 8 10] [5 12 13] [9 12 15] [8 15 17] [12 16 20] [7 24 25] [15 20 25] [10 24 26] [20 21 29]}