منابع مشابه
There May Be No Hausdorff Ultrafilters
An ultrafilter U is Hausdorff if for any two functions f, g ∈ ω ω , f (U) = g(U) iff f ↾X = g↾X for some X ∈ U. We will show that it is consistent that there are no Hausdorff ultrafilters.
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ژورنال
عنوان ژورنال: Proceedings of the American Mathematical Society
سال: 2006
ISSN: 0002-9939,1088-6826
DOI: 10.1090/s0002-9939-06-08433-4