A characterization of the least cardinal for which the Baire category theorem fails
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چکیده
منابع مشابه
A Characterization of the Least Cardinal for Which the Baire Category Theorem Fails
Let k be the least cardinal such that the real Une can be covered by k many nowhere dense sets. We show that k can be characterized as the least cardinal such that "infinitely equal" reals fail to exist for families of cardinality k. Let Baire (k) stand for: "The real line is not the union of k many nowhere dense sets (a set is nowhere dense iff its closure has no interior)". The property was e...
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ژورنال
عنوان ژورنال: Proceedings of the American Mathematical Society
سال: 1982
ISSN: 0002-9939
DOI: 10.1090/s0002-9939-1982-0671224-2