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arXiv · 2304.02143

A note on special subsets of the Rudin-Frol\'ik order for regulars

Joanna Jureczko
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Abstract

We show that there is a set of $2^{2^{\kappa}}$ ultrafilters incomparable in Rudin-Frol\'ik order of $\beta \kappa \setminus \kappa$, where $\kappa$ is regular, for which no subset with more than one element has an infimum.

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Joanna Jureczko. 2023-03-28. A note on special subsets of the Rudin-Frol\'ik order for regulars. https://arxiv.org/abs/2304.02143

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