Aspects of singular cofinality
نویسنده
چکیده
We study properties of closure operators of singular cofinality, and introduce several ZFC sufficient and equivalent conditions for the existence of antichain sequences in posets of singular cofinality. We also notice that the Proper Forcing Axiom implies the Milner-Sauer conjecture.
منابع مشابه
Successors of singular cardinals and coloring theorems {II}
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عنوان ژورنال:
- Contributions to Discrete Mathematics
دوره 2 شماره
صفحات -
تاریخ انتشار 2007