proposition: Lemma opow_succ x y: ordinalp x -> ordinalp y -> x ^o (osucc y) = (x ^o y) *o x.
proof: Proof. by move=> ox oy;rewrite -(osucc_pr oy) (opow_sum ox oy OS1) opowx1. Qed.
imports: mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat)