proposition: Lemma dualelement_sn_le {m n k q: nat} (lt : S n < S k) : pr1 (dualelement (n,, lt)) <= (pr1 (dualelement (S n,, lt))).
proof: Proof. rewrite (@dualelement_sn_eq n n k k lt). apply isreflnatleh. Defined.
imports: UniMath.Foundations.All UniMath.MoreFoundations.All UniMath.Combinatorics.Maybe UniMath.Combinatorics.StandardFiniteSets UniMath.Algebra.Domains_and_Fields UniMath.Algebra.RigsAndRings