proposition: Lemma lt_1_3 : 1 < 3.
proof: Proof. now apply pos_plus_lt_compat_r, lt_0_2. Qed.
imports: Coq.setoid_ring.Ring MathClasses.interfaces.abstract_algebra MathClasses.interfaces.orders MathClasses.theory.rings MathClasses.orders.orders MathClasses.orders.maps