proposition: Lemma snlehm_to_nltm (m n : nat) : (S n ≤ m) -> n < m.
proof: Proof. intros le_sn_m; exact le_sn_m. Defined.
imports: UniMath.Foundations.All UniMath.MoreFoundations.All UniMath.Combinatorics.Maybe UniMath.Combinatorics.StandardFiniteSets UniMath.Algebra.Domains_and_Fields UniMath.Algebra.RigsAndRings