proposition: Lemma intr_norm m : `|m|%:~R = `|m%:~R : R|.
proof: Proof. by rewrite {2}[m]intEsign rmorphMsign normrMsign abszE normr_nat. Qed.
imports: HB(structures) mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat choice seq) mathcomp(fintype finfun bigop order ssralg countalg ssrnum) mathcomp(poly)