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A note on kappa-freeness

Saharon Shelah
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Abstract

In this short note we show that if lambda>aleph_1 is regular and lambda is not the successor of a singular cardinal of cofinality aleph_0, and G is a lambda-free abelian group of size lambda, then there is a free group G' subseteq G of size lambda.

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Saharon Shelah. 2004-04-09. A note on kappa-freeness. https://arxiv.org/abs/math/0404207

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