proposition: Lemma sigma_ctrl_init : forall s0 : Site, sigma_ctrl s0 bag_init = 0%Z.
proof: Proof. intros; unfold sigma_ctrl in |- *; rewrite sigma_ctrl_copy_init; rewrite sigma_ctrl_dec_init; rewrite sigma_ctrl_inc_init; omega. Qed.
imports: DistributedReferenceCounting.machine0.machine counting