proposition: Lemma sigma_finite_counting (R : realType) : sigma_finite [set: nat] (@counting _ R).
proof: Proof. exists (fun n => `I_n.+1); first by apply/seteqP; split=> //x _; exists x => /=. by move=> k; split => //; rewrite /counting/= asboolT// ltry. Qed.
imports: mathcomp(all_ssreflect all_algebra finmap) mathcomp(mathcomp_extra boolp classical_sets functions) mathcomp(cardinality fsbigop ) reals ereal signed topology normedtype sequences esum numfun HB(structures)