proposition: Lemma msuppU1 k : @msupp _ R << k >> = [fset k].
proof: Proof. by rewrite msuppU oner_eq0. Qed.
imports: HB(structures) mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat) mathcomp(seq path choice finset fintype finfun) mathcomp(tuple bigop ssralg ssrint ssrnum) xfinmap