proposition: Lemma comp_mpolyXU i lq : 'X_i \mPo lq = lq`_i.
proof: Proof. by rewrite /comp_mpoly mmapX mmap1U -tnth_nth. Qed.
imports: HB(structures) mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat seq path) mathcomp(choice fintype tuple finfun bigop finset binomial) mathcomp(order fingroup perm ssralg zmodp poly ssrint) mathcomp(matrix vector) mathcomp(bigenough) ssrcomplements freeg