proposition: Lemma Rnat_ltE (c d : N) : (c < d)%C = (spec_N c < spec_N d).
proof: Proof. symmetry; eapply refines_eq. change (spec_N c < spec_N d) with (rel_of_simpl ltn (spec_N c) (spec_N d)). refines_apply1; first refines_apply1. refines_abstr. Qed.
imports: ZArith Lia mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat div seq zmodp) mathcomp(path choice fintype tuple finset ssralg ssrnum bigop ssrint) CoqEAL(hrel param refinements pos)