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Proceedings of the American Mathematical Society

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Cohesive sets: countable and uncountable


Author: Richard A. Shore
Journal: Proc. Amer. Math. Soc. 44 (1974), 442-445
MSC: Primary 02F27; Secondary 02K05, 02K35
MathSciNet review: 0342382
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Abstract: We show that many uncountable admissible ordinals (including some cardinals) as well as all countable admissible ordinals have cohesive subsets. Exactly which cardinals have cohesive subsets, however, is shown to depend on set-theoretic assumptions such as $ V = L$ or a large cardinal axiom.


References [Enhancements On Off] (What's this?)

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Additional Information

DOI: https://doi.org/10.1090/S0002-9939-1974-0342382-X
Keywords: Admissible ordinal, cohesive set
Article copyright: © Copyright 1974 American Mathematical Society