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arXiv · 1911.01206

Cardinal functions of purely atomic measures

Szymon Głab·Jacek Marchwicki
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Abstract

Let $\mu$ be a purely atomic measure. By $f_\mu:[0,\infty)\to\{0,1,2,\dots,\omega,\mathfrak{c}\}$ we denote its cardinal function $f_{\mu}(t)=\vert\{A\subset\mathbb N:\mu(A)=t\}\vert$. We study the problem for which sets $R\subset\{0,1,2,\dots,\omega,\mathfrak{c}\}$ there is a measure $\mu$ such that $R$ is the range of $f_\mu$. We are also interested in the set-theoretic and topological properties of the set of $\mu$-values which are obtained uniquely.

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Szymon Głab, Jacek Marchwicki. 2019-11-04. Cardinal functions of purely atomic measures. https://arxiv.org/abs/1911.01206

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