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arXiv · 2009.13686

Tall $F_\sigma$ subideals of tall analytic ideals

Jan Grebík·Zoltán Vidnyánszky
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Abstract

Answering a question of Hru\v{s}\'ak, we show that every analytic tall ideal on $\omega$ contains an $F_\sigma$ tall ideal. We also give an example of an $F_\sigma$ tall ideal without a Borel selector.

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Jan Grebík, Zoltán Vidnyánszky. 2020-09-28. Tall $F_\sigma$ subideals of tall analytic ideals. https://arxiv.org/abs/2009.13686

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