Zulip Chat Archive

Stream: Is there code for X?

Topic: A limit of a series


Michael Stoll (Dec 21 2023 at 16:12):

I managed to produce a proof of the following:

import Mathlib

open Filter Set Topology in
lemma partialZetaSum_inv_tendsto_zero_of_not_summable {A : Set }
    (hA : ¬ Summable (indicator A fun n :   1 / (n : ))) :
    Tendsto (fun s :   (∑' n, indicator A (fun n  (n : ) ^ (-s)) n)⁻¹) (𝓝[>] 1) (𝓝 0) := by
  sorry

but it is perhaps a bit clumsy (I'm going back to epsilons and deltas), and I was wondering if there is a more elegant way using the filter machinery. Any suggestions?


Last updated: May 02 2025 at 03:31 UTC