arXiv math/04042072004-04-09math.LOmath.GR

A note on kappa-freeness

Saharon Shelah

英文摘要：

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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