proposition: Lemma cnf_coef_of_lc x: cnfp_nz x -> cnf_lc x = Vr x (cnf_degree x).
proof: Proof. move => xnz. by rewrite /cnf_lc (Vr_correct (proj1 xnz) (cnf_size_nz_bis xnz)). Qed.
imports: mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat)