proposition: Lemma card_classCT_neq0 : #|classCT| != 0%N.
proof: Proof. Proof using. by rewrite cards_eq0; apply /set0Pn; exists permCT; apply: class_refl. Qed.
imports: mathcomp.ssreflect.ssreflect mathcomp(ssrfun ssrbool eqtype ssrnat seq choice fintype) mathcomp(tuple finfun finset path bigop) mathcomp(fingroup perm action) mathcomp(ssralg matrix mxalgebra algC classfun) partition tools sorted permcomp fibered_set cycles