proposition: Fact normzN m : normz (- m) = normz m.
proof: Proof. by case: m => // -[]. Qed.
imports: HB(structures) mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat choice seq) mathcomp(fintype finfun bigop order ssralg countalg ssrnum) mathcomp(poly)