Abstract
We prove that \(\mathfrak{mcf}\) and \(\mathfrak{mcf}\) are both consistent relative to ZFC. This answers a question by Banakh, Repovš and Zdomskyy and a question from [MS11].
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We thank the referee for numerous valuable hints.
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The first author’s research is supported by an Internal Senior Fellowship of the Freiburg Institute of Advanced Studies.
The second author’s research was partially supported by the United States-Israel Binational Science Foundation (Grant no. 2002323). This is the second authors publication no. 1021.
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Mildenberger, H., Shelah, S. The cofinality of the symmetric group and the cofinality of ultrapowers. Isr. J. Math. 242, 97–128 (2021). https://doi.org/10.1007/s11856-021-2124-2
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DOI: https://doi.org/10.1007/s11856-021-2124-2