Combinatorially rich sets in partial semigroups
Combinatorics
2025-02-07 v2
Abstract
There are several notions of size for semigroups that have natural analogues for partial semigroups. Among these are thick, syndetic, central, piecewise syndetic, IP, J, and the more recently introduced notion of combinatorially rich, abbreviated CR. We investigate the notion of CR set for adequate partial semigroups, its relation to other notions, especially J sets, and some surprising differences among them.
Keywords
Cite
@article{arxiv.2307.01096,
title = {Combinatorially rich sets in partial semigroups},
author = {Arpita Ghosh and Neil Hindman},
journal= {arXiv preprint arXiv:2307.01096},
year = {2025}
}
Comments
17 pages, comments are welcome