proposition: Lemma labelling_empty: forall f, (forall a, f a = false) -> forall n, labelling n f == 0.
proof: Proof. intros. apply sum_zero. intros m _. rewrite H. reflexivity. Qed.
imports: ATBR(Common) ATBR(Classes) ATBR(Graph) ATBR(Monoid) ATBR(SemiLattice) ATBR(SemiRing) ATBR(KleeneAlgebra) ATBR(MxGraph) ATBR(MxSemiLattice) ATBR(MxSemiRing) ATBR(MxKleeneAlgebra) ATBR(DKA_Definitions) ATBR(DKA_CheckLabels) ATBR(StrictStarForm) ATBR(Utils_WF) Coq(Relations)