proposition: Lemma abszMsign s m : `|((-1) ^+ s * m)%R| = `|m|.
proof: Proof. by rewrite abszM absz_sign mul1n. Qed.
imports: HB(structures) mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat choice seq) mathcomp(fintype finfun bigop order ssralg countalg ssrnum) mathcomp(poly)