proposition: Lemma expv_line u n : (<[u]> ^+ n = <[u ^+ n]>)%VS.
proof: Proof. elim: n => [|n IH]; first by rewrite expr0 expv0. by rewrite exprS expvSl IH prodv_line. Qed.
imports: HB(structures) mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat seq path) mathcomp(choice fintype div tuple finfun bigop ssralg) mathcomp(finalg zmodp matrix vector poly)