Groupwise density cannot be much bigger than the unbounded number
نویسنده
چکیده
We prove that g (the groupwise density number) is smaller or equal to b, the successor of the minimal cardinality of an unbounded subset of ωω. This is true even for the version of g for groupwise dense ideals.
منابع مشابه
Groupwise density and related cardinals
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عنوان ژورنال:
- Math. Log. Q.
دوره 54 شماره
صفحات -
تاریخ انتشار 2008