proposition: Lemma summable0 : summable (fun _ : T => 0 : R).
proof: Proof. by exists 0 => J; rewrite big1 ?normr0. Qed.
imports: mathcomp(all_ssreflect all_algebra) mathcomp.classical(boolp) xfinmap ereal reals discrete realseq mathcomp.classical(classical_sets functions mathcomp_extra) topology