Ultrafilters on a countable set
نویسندگان
چکیده
منابع مشابه
Walks on Countable Ordinals and Selective Ultrafilters
In our previous work we have introduced filters on the set of countable ordinals as invariants to standard characteristics of walks in this domain. In this note we examine their projections to the set of natural numbers.
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ژورنال
عنوان ژورنال: Annals of Mathematical Logic
سال: 1970
ISSN: 0003-4843
DOI: 10.1016/0003-4843(70)90005-7