Talk : Pythagorean triple. (a) The odd leg a. (b) The b-is-even convention. (c) Proofs around Euclid's formula are incomplete. (d) The source "Proof by infinite descent" makes a serious mistake. (e) Usimg the m,n-substitution one needs only one given more (not two) to solve the problem. (f) The triangles op Pythagoras and Plato are incorrectly explained and the text contains a serious mistake Please use in mathematics brains no sources.