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arXiv · 2205.10709

Unlimited accumulation by the Shelah's PCF operator

Mohammad Golshani
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Abstract

Modulo the existence of large cardinals, there is a model of set theory in which for some set $B$ of regular cardinals, the sequence $\langle \text{pcf}^\alpha(B): \alpha \in \text{Ord} \rangle$ is strictly increasing. The result answers a question from [7].

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Mohammad Golshani. 2022-05-22. Unlimited accumulation by the Shelah's PCF operator. https://arxiv.org/abs/2205.10709

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