proposition: Lemma negate_to_ring_nonpos n : -f n ≤ 0.
proof: Proof. apply flip_nonneg_negate. apply to_semiring_nonneg. Qed.
imports: HoTT.Types.Sigma HoTT.Classes.theory.naturals HoTT.Classes.interfaces.abstract_algebra HoTT.Classes.interfaces.orders HoTT.Classes.theory.rings HoTT.Classes.orders.rings HoTT.Classes.implementations.peano_naturals HoTT.Classes.orders.nat_int