proposition: Fact mxOver_mul_subproof : mulr_closed (@mxOver n.+1 n.+1 _ S).
proof: Proof. by split; rewrite ?mxOver_scalar ?rpred0 ?rpred1//; apply: mxOverM. 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 countalg finalg zmodp)