English

Operations preserving equivalence relations

Combinatorics 2017-06-01 v1

Abstract

In 2014, C\'egielski, Grigorieff and Guessarian characterized unary self-maps on the set Z\mathbb{Z} of integers which preserve all congruences of the additive group. In this note, we propose a shorter and straigthforward proof. We replace this result in the frame of universal algebra.

Cite

@article{arxiv.1705.10890,
  title  = {Operations preserving equivalence relations},
  author = {Maurice Pouzet},
  journal= {arXiv preprint arXiv:1705.10890},
  year   = {2017}
}

Comments

14 pages

R2 v1 2026-06-22T20:04:18.594Z