proposition: Lemma eq_row_sub m n v (A : 'M_(m, n)) i : row i A = v -> (v <= A)%MS.
proof: Proof. by move <-; rewrite row_sub. Qed.
imports: HB(structures) mathcomp(ssreflect ssrbool ssrfun eqtype ssrnat seq choice) mathcomp(fintype finfun bigop finset fingroup perm order) mathcomp(div prime binomial ssralg finalg zmodp matrix)