proposition: Lemma mul0rz n : 0 *~ n = 0 :> M.
proof: Proof. by rewrite -scalezrE scaler0. Qed.
imports: HB(structures) mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat choice seq) mathcomp(fintype finfun bigop order ssralg countalg ssrnum) mathcomp(poly)