Almost disjoint refinement of families of subsets of $\textbf {N}$
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- by Bohuslav Balcar and Peter Vojtáš PDF
- Proc. Amer. Math. Soc. 79 (1980), 465-470 Request permission
Abstract:
Without any set-theoretic assumptions, we prove that every uniform ultrafilter on the set N of all natural numbers has a Comfort system, that is, an almost disjoint refinement. Moreover, we describe one type of ideal such that the family of all subsets of N that are not contained in it has an almost disjoint refinement.References
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Additional Information
- © Copyright 1980 American Mathematical Society
- Journal: Proc. Amer. Math. Soc. 79 (1980), 465-470
- MSC: Primary 04A20; Secondary 54A25, 54D40
- DOI: https://doi.org/10.1090/S0002-9939-1980-0567994-2
- MathSciNet review: 567994