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A Note on Special Subsets of the Rudin-Frolík Order for Regulars

  • Joanna Jureczko
Published/Copyright: August 4, 2023
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Mathematica Slovaca
From the journal Mathematica Slovaca Volume 73 Issue 4

ABSTRACT

We show that there is a set of 22 κ ultrafilters incomparable in the Rudin-Frolík order of βκ\κ, where κ is regular, for which no subset with more than one element has an infimum.

2020 Mathematics Subject Classification: Primary 03E10; 03E20; 03E30
Keywords: Ultrafilters; regular cardinal; the Rudin-Frolík order; independent family

(Communicated by L’ubica Holá)

Acknowledgement

The author is very grateful to the anonymous reviewers for their insight in reading the previous version of this paper. Their remarks undoubtedly avoided many inaccuracies and made the text more readable.

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Received: 2022-02-07
Accepted: 2022-09-19
Published Online: 2023-08-04

© 2023 Mathematical Institute Slovak Academy of Sciences

Articles in the same Issue

  1. A Note on Special Subsets of the Rudin-Frolík Order for Regulars
  2. The 2-Class Group of Certain Families of Imaginary Triquadratic Fields
  3. The Deranged Bell Numbers
  4. On Index and Monogenity of Certain Number Fields Defined by Trinomials
  5. The k-Generalized Lucas Numbers Close to a Power of 2
  6. Shifted Power of a Polynomial with Integral Roots
  7. Further Insights into the Mysteries of the Values of Zeta Functions at Integers
  8. Memoryless Properties on Time Scales
  9. A Study of the Higher-Order Schwarzian Derivatives of Hirotaka Tamanoi
  10. Besov and Triebel-Lizorkin Capacity in Metric Spaces
  11. Oscillation of Odd Order Linear Differential Equations with Deviating Arguments with Dominating Delay Part
  12. An Elliptic Type Inclusion Problem on the Heisenberg Lie Group
  13. Existence Result for a Double Phase Problem Involving the (p(x), q(x))-Laplacian Operator
  14. A New Series Space Derived by Absolute Generalized Nörlund Means
  15. Examples of Weinstein Domains in the Complement of Smoothed Total Toric Divisors
  16. The Uniform Effros Property and Local Homogeneity
  17. Limit Theorems for Weighted Sums of Asymptotically Negatively Associated Random Variables Under Some General Conditions
  18. The Unit-Gompertz Quantile Regression Model for the Bounded Responses
  19. An Extended Gamma-Lindley Model and Inference for the Prediction of Covid-19 in Tunisia
  20. Modeling Bivariate Data Using Linear Exponential and Weibull Distributions as Marginals
https://doi.org/10.1515/ms-2023-0060
Keywords for this article
Ultrafilters; regular cardinal; the Rudin-Frolík order; independent family

Articles in the same Issue

  1. A Note on Special Subsets of the Rudin-Frolík Order for Regulars
  2. The 2-Class Group of Certain Families of Imaginary Triquadratic Fields
  3. The Deranged Bell Numbers
  4. On Index and Monogenity of Certain Number Fields Defined by Trinomials
  5. The k-Generalized Lucas Numbers Close to a Power of 2
  6. Shifted Power of a Polynomial with Integral Roots
  7. Further Insights into the Mysteries of the Values of Zeta Functions at Integers
  8. Memoryless Properties on Time Scales
  9. A Study of the Higher-Order Schwarzian Derivatives of Hirotaka Tamanoi
  10. Besov and Triebel-Lizorkin Capacity in Metric Spaces
  11. Oscillation of Odd Order Linear Differential Equations with Deviating Arguments with Dominating Delay Part
  12. An Elliptic Type Inclusion Problem on the Heisenberg Lie Group
  13. Existence Result for a Double Phase Problem Involving the (p(x), q(x))-Laplacian Operator
  14. A New Series Space Derived by Absolute Generalized Nörlund Means
  15. Examples of Weinstein Domains in the Complement of Smoothed Total Toric Divisors
  16. The Uniform Effros Property and Local Homogeneity
  17. Limit Theorems for Weighted Sums of Asymptotically Negatively Associated Random Variables Under Some General Conditions
  18. The Unit-Gompertz Quantile Regression Model for the Bounded Responses
  19. An Extended Gamma-Lindley Model and Inference for the Prediction of Covid-19 in Tunisia
  20. Modeling Bivariate Data Using Linear Exponential and Weibull Distributions as Marginals
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