proposition: Lemma tofracMNn n : {morph tofrac: x / x *- n}.
proof: Proof. exact: rmorphMNn. Qed.
imports: HB(structures) mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat div seq) mathcomp(ssrAC choice tuple bigop ssralg poly polydiv) mathcomp(generic_quotient)