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arXiv · 1304.5683

Around cofin

Andrzej Roslanowski·Saharon Shelah
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Abstract

We show the consistency of "there is a nice sigma --ideal I on the reals with add(I)= omega_1 which cannot be represented as the union of a strictly increasing sequence of length omega_1 of sigma-subideals". This answers a question by Borodulin-Nadzieja and Glab.

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Andrzej Roslanowski, Saharon Shelah. 2013-04-21. Around cofin. https://arxiv.org/abs/1304.5683

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