On strongly summable ultrafilters and union ultrafilters
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- by Andreas Blass and Neil Hindman PDF
- Trans. Amer. Math. Soc. 304 (1987), 83-97 Request permission
Abstract:
We prove that union ultrafilters are essentially the same as strongly summable ultrafilters but ordered-union ultrafilters are not. We also prove that the existence of ultrafilters of these sorts implies the existence of $P$-points and therefore cannot be established in ZFC.References
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Additional Information
- © Copyright 1987 American Mathematical Society
- Journal: Trans. Amer. Math. Soc. 304 (1987), 83-97
- MSC: Primary 03E05; Secondary 03E35, 03E50
- DOI: https://doi.org/10.1090/S0002-9947-1987-0906807-4
- MathSciNet review: 906807