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Lusin sequences under CH and under Martin's Axiom

Uri Abraham·Saharon Shelah
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Abstract

Assuming the continuum hypothesis there is an inseparable sequence of length omega_1 that contains no Lusin subsequence, while if Martin's Axiom and the negation of CH is assumed then every inseparable sequence (of length omega_1) is a union of countably many Lusin subsequences.

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BibTeXRIS

Uri Abraham, Saharon Shelah. 1998-07-15. Lusin sequences under CH and under Martin's Axiom. https://arxiv.org/abs/math/9807178

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