proposition: Lemma cycle_eq1 x : (<[x]> == 1) = (x == 1).
proof: Proof. by rewrite eqEsubset sub1G andbT cycle_subG inE. Qed.
imports: HB(structures) mathcomp(ssreflect ssrbool ssrfun eqtype ssrnat seq choice) mathcomp(fintype div path tuple bigop prime finset)