proposition: Lemma cast_row_mx m m' n1 n2 (eq_m : m = m') A1 A2 : castmx (eq_m, erefl _) (row_mx A1 A2) = row_mx (castmx (eq_m, erefl n1) A1) (castmx (eq_m, erefl n2) A2).
proof: Proof. by case: m' / eq_m. 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)