proposition: Lemma lin_subst sigma S t: sigma • lin S t = lin (sigma •₊ S) (sigma • t).
proof: Proof. unfold lin; asimpl; now rewrite !map_map. Qed.
imports: RelationClasses Morphisms List Lia Init.Nat Setoid Undecidability.HOU(calculus.calculus second_order.diophantine_equations systemunification nth_order_unification)