Ordinal ultrafilters versus P-hierarchy
نویسندگان
چکیده
منابع مشابه
A Few Special Ordinal Ultrafilters
We prove various results on the notion of ordinal ultraaters introduced by J. Baumgartner. In particular, we show that this notion of ultraalter complexity is independent of the more familiar Rudin-Keisler ordering. 1. Introduction Interesting ultraalters are those comprising rich combinatorial properties of some sort. Traditional criterions consist of partition relations on the natural numbers...
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ژورنال
عنوان ژورنال: Open Mathematics
سال: 2014
ISSN: 2391-5455
DOI: 10.2478/s11533-013-0320-y