Ultrafilters and almost disjoint sets
نویسندگان
چکیده
منابع مشابه
Almost disjoint families on large underlying sets
We show that, for any poset P, the existence of a P-indestructible mad family F ⊆ [ω]א0 is equivalent to the existence of such a family over אn for some/all n ∈ ω. Under the very weak square principle ¤∗∗∗ ω1,μ of Fuchino and Soukup [7] and cf([μ]א0 ,⊆) = μ+ for all limit cardinals μ of cofinality ω, the equivalence for any proper poset P transfers to all cardinals. That is, under these assumpt...
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ژورنال
عنوان ژورنال: General Topology and its Applications
سال: 1974
ISSN: 0016-660X
DOI: 10.1016/0016-660x(74)90026-9