proposition: Lemma card_Aut_cyclic : cyclic G -> #|Aut G| = totient #|G|.
proof: Proof. by case/cyclicP=> x ->; apply: card_Aut_cycle. Qed.
imports: HB(structures) mathcomp(ssreflect ssrbool ssrfun eqtype ssrnat seq choice div) mathcomp(fintype bigop prime finset fingroup morphism) mathcomp(perm automorphism quotient gproduct ssralg) mathcomp(finalg zmodp poly)