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arXiv · 2305.02794

Ultrafilters without immediate predecessors in Rudin-Frolik order for regulars

Joanna Jureczko
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Abstract

The aim of this paper is to construct ultrafilters without immediate predecessors in the Rudin-Frolik order in $\beta \kappa\setminus \kappa$, where $\kappa$ is a regular cardinal. This generalizes the problem posed by Peter Simon more than 40 years ago.

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Joanna Jureczko. 2023-03-28. Ultrafilters without immediate predecessors in Rudin-Frolik order for regulars. https://arxiv.org/abs/2305.02794

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