proposition: Lemma dvdmx_refl m n (M : 'M[R]_(m,n)) : M %| M .
proof: Proof. by apply/dvdmxP; exists 1%:M; rewrite mul1mx. Qed.
imports: HB(structures) mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat div seq path) mathcomp(ssralg fintype perm choice matrix bigop zmodp mxalgebra poly) ssrcomplements dvdring stronglydiscrete