proposition: Lemma negate_to_ring_nonpos n : -f n ≤ 0.
proof: Proof. apply flip_nonneg_negate. now apply to_semiring_nonneg. Qed.
imports: Coq.setoid_ring.Ring MathClasses.interfaces.abstract_algebra MathClasses.interfaces.naturals MathClasses.interfaces.orders MathClasses.orders.rings MathClasses.orders.nat_int