English

On the number of countable subdirect powers of unary algebras

Rings and Algebras 2023-07-11 v3

Abstract

A finite unary algebra (A,F)(A,F) has only countably many countable subdirect powers if and only if every operation fFf\in F is either a permutation or a constant mapping.

Keywords

Cite

@article{arxiv.2106.08876,
  title  = {On the number of countable subdirect powers of unary algebras},
  author = {Nik Ruskuc and Bill de Witt},
  journal= {arXiv preprint arXiv:2106.08876},
  year   = {2023}
}