2 citations · 7 across the 22 of their papers we have counts for
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Counting coarse subsets of a countable group
Igor Protasov, Ksenia Protasova
For every countable group , there are distinct classes of coarsely equivalent subsets of .
Ramsey-product subsets of a group
Igor Protasov, Ksenia Protasova
We say that a subset of an infinite group is a Ramsey-product subset if, for any infinite subsets , of , there exist and such that …
On recurrence in G-spaces
Igor Protasov, Ksenia Protasova
We introduce and analyze the following general concept of recurrence. Let be a group and let be a G-space with the action , $(g,x)\longmapsto gx…
The descriptive look at the size of subsets of groups
Igor Protasov, Taras Banakh, Ksenia Protasova
We explore the Borel complexity of some basic families of subsets of a countable group (large, small, thin, sparse and other) defined by the size of their elements. Applying the ob…
On hyperballeans of bounded geometry
Igor Protasov, Ksenia Protasova
A ballean (or coarse structure) is a set endowed with some family of subsets, the balls, is such a way that balleans with corresponding morphisms can be considered as asymptotic co…