proposition: Lemma eqz_mul d m n : d != 0 -> (d %| m)%Z -> (m == n * d) = (m %/ d == n)%Z.
proof: Proof. by move=> d_gt0 dv_d_m; rewrite eq_sym -eqz_div // eq_sym. Qed.
imports: HB(structures) mathcomp(ssreflect ssrbool ssrfun eqtype ssrnat seq path) mathcomp(div choice fintype tuple finfun bigop prime order) mathcomp(ssralg poly ssrnum ssrint archimedean rat matrix) mathcomp(polydiv perm zmodp mxalgebra vector)