proposition: Lemma scale0r v : 0 *: v = 0.
proof: Proof. by apply: (addIr (1 *: v)); rewrite -scalerDl !add0r. Qed.
imports: HB(structures) mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat div seq) mathcomp(choice fintype finfun bigop prime binomial)