English

Another characterization of meager ideals

General Topology 2021-09-14 v1 Functional Analysis

Abstract

We show that an ideal I\mathcal{I} on the positive integers is meager if and only if there exists a bounded nonconvergent real sequence xx such that the set of subsequences [resp. permutations] of xx which preserve the set of I\mathcal{I}-limit points is comeager and, in addition, every accumulation point of xx is also an I\mathcal{I}-limit point (that is, a limit of a subsequence (xnk)(x_{n_k}) such that {n1,n2,,}I\{n_1,n_2,\ldots,\} \notin \mathcal{I}). The analogous characterization holds also for I\mathcal{I}-cluster points.

Keywords

Cite

@article{arxiv.2109.05266,
  title  = {Another characterization of meager ideals},
  author = {Marek Balcerzak and Szymon Glab and Paolo Leonetti},
  journal= {arXiv preprint arXiv:2109.05266},
  year   = {2021}
}

Comments

10pp

R2 v1 2026-06-24T05:52:52.690Z