proposition: Lemma merge2_nothing (F: graph2) (h: pairs F): List.Forall (fun p => p.1 = p.2) h -> merge2_seq F h ≃2 F.
proof: Proof. destruct F. apply merge_nothing. Defined.
imports: HB(structures) Coq(Setoid Morphisms) mathcomp(all_ssreflect) GraphTheory(edone finite_quotient preliminaries bij equiv) GraphTheory(setoid_bigop structures pttdom mgraph ptt)