proposition: Lemma intrN n : (- n)%:~R = - n%:~R :> R.
proof: Proof. exact: mulrNz. Qed.
imports: HB(structures) mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat choice seq) mathcomp(fintype finfun bigop order ssralg countalg ssrnum) mathcomp(poly)