6 citations · 18 across the 7 of their papers we have counts for
7 papers
Densities for sets of natural numbers vanishing on a given family
Rafał Filipów, Jacek Tryba
Abstract upper densities are monotone and subadditive functions from the power set of positive integers into the unit real interval that generalize the upper densities used in numb…
New Hindman spaces
Rafał Filipów, Krzysztof Kowitz, Adam Kwela +1
We introduce a method that allows to turn topological questions about Hindman spaces into purely combinatorial questions about the Katětov order of ideals on . We also…
Characterizing existence of certain ultrafilters
Rafał Filipów, Krzysztof Kowitz, Adam Kwela
Following Baumgartner [J. Symb. Log. 60 (1995), no. 2], for an ideal on , we say that an ultrafilter on is an -ultrafilter if for ev…
Spaces not distinguishing ideal pointwise and -uniform convergence
Rafał Filipów, Adam Kwela
We examine topological spaces not distinguishing ideal pointwise and ideal -uniform convergence of sequences of real-valued continuous functions defined on them. For instance, w…
Yet another ideal version of the bounding number
Rafał Filipów, Adam Kwela
Let be an ideal on . For we write if for all with some . Moreover, we den…
A unified approach to Hindman, Ramsey and van der Waerden spaces
Rafał Filipów, Krzysztof Kowitz, Adam Kwela
For many years, there have been conducting research (e.g. by Bergelson, Furstenberg, Kojman, Kubiś, Shelah, Szeptycki, Weiss) into sequentially compact spaces that are, in a sense,…