proposition: Lemma Frobenius_aut_is_additive : additive (Frobenius_aut charRp).
proof: Proof. move=> x y; exact: Frobenius_autB_comm (mulrC _ _). Qed.
imports: HB(structures) mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat div seq) mathcomp(choice fintype finfun bigop prime binomial)