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arXiv · 1312.6780

The spectrum of ultraproducts of finite cardinals for an ultrafilter

Saharon Shelah
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Abstract

We complete the characterization of the possible spectrum of regular ultrafilters D on a set I, where the spectrum is the set of infinite cardinals which are ultraproducts of finite cardinals modulo D.

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Saharon Shelah. 2021-09-02. The spectrum of ultraproducts of finite cardinals for an ultrafilter. https://doi.org/10.1007/s10474-018-0847-2

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