proposition: Lemma mpolyXn m i : 'X_[m] ^+ i = 'X_[m *+ i].
proof: Proof. elim: i=> [|i ih]; first by rewrite expr0 mulm0n mpolyX0. by rewrite mulmS mpolyXD -ih exprS. Qed.
imports: HB(structures) mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat seq path) mathcomp(choice fintype tuple finfun bigop finset binomial) mathcomp(order fingroup perm ssralg zmodp poly ssrint) mathcomp(matrix vector) mathcomp(bigenough) ssrcomplements freeg