English

The partitions whose members are finite and the permutations with at most $n$ non-fixed points of a set

Logic 2023-12-05 v1

Abstract

We write Sn(A)S_{\leq n}(A) and \Part\fin(A)\Part_{\fin}(A) for the set of permutations with at most nn non-fixed points, where nn is a natural number, and the set of partitions whose members are finite, respectively, of a set AA. Among our results, we show, in the Zermelo-Fraenkel set theory, that \Part\fin(A)Sn(A)|\Part_{\fin}(A)| \nleq |S_{\leq n}(A)| for any infinite set AA and if AA can be linearly ordered, then Sn(A)<\Part\fin(A)|S_{\leq n}(A)| < |\Part_{\fin}(A)| while the statement ``Sn(A)\Part\fin(A)|S_{\leq n}(A)|\leq|\Part_{\fin}(A)| for all infinite sets AA" is not provable for n3n\geq 3.

Keywords

Cite

@article{arxiv.2312.01349,
  title  = {The partitions whose members are finite and the permutations with at most $n$ non-fixed points of a set},
  author = {Nattapon Sonpanow and Pimpen Vejjajiva},
  journal= {arXiv preprint arXiv:2312.01349},
  year   = {2023}
}