proposition: Lemma nd_nnsfun_approx : nondecreasing_seq (nnsfun_approx : (T -> R)^nat).
proof: Proof. move=> m n mn; rewrite (nnsfun_approxE n) (nnsfun_approxE m). exact: nd_approx. Qed.
imports: HB(structures) mathcomp(all_ssreflect ssralg ssrnum ssrint interval finmap) mathcomp(mathcomp_extra boolp classical_sets functions) mathcomp(cardinality fsbigop ) signed reals ereal topology normedtype sequences real_interval esum measure lebesgue_measure numfun