proposition: Lemma order_inf a n : a ^+ n.+1 == 1 -> #[a] <= n.+1.
proof: Proof. by rewrite -order_dvdn; apply: dvdn_leq. 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)