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Generating ultrafilters in a reasonable way

Andrzej Roslanowski·Saharon Shelah
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Abstract

We continue investigations of reasonable ultrafilters on uncountable cardinals defined in Shelah math.LO/0407498 and studied also in math.LO/0605067. We introduce a general scheme of generating a filter on lambda from filters on smaller sets and we investigate the combinatorics of objects obtained this way.

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Andrzej Roslanowski, Saharon Shelah. 2007-09-16. Generating ultrafilters in a reasonable way. https://arxiv.org/abs/math/0607218

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