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arXiv · 2512.07711

$\sigma$-Porosity of Certain Ideals

Paweł Klinga·Andrzej Nowik·Anna Wąsik
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Abstract

We investigate the $\sigma$-porosity of certain known ideals of subsets of natural numbers. Porosity is a notion of smallness in metric spaces that is stronger than nowhere density. Analogously, $\sigma$-porosity is a strengthening of meagerness. In this paper, we verify which ideals are $\sigma$-porous.

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Paweł Klinga, Andrzej Nowik, Anna Wąsik. 2025-12-08. $\sigma$-Porosity of Certain Ideals. https://arxiv.org/abs/2512.07711

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