proposition: Lemma inj_prodAC : injective prodAC.
proof: Proof. by move=> -[[? ?] ?] [[? ?] ?] [-> -> ->]. Qed.
imports: mathcomp(all_ssreflect ssralg fingroup perm matrix) mathcomp(all_algebra vector reals normedtype) mathcomp(mathcomp_extra boolp) mathcomp(Rstruct) ssrR logb realType_ext ssr_ext ssralg_ext bigop_ext