English

On finite groups with exactly one noncommutator

Group Theory 2025-09-23 v1

Abstract

An element xx of a group GG is a commutator if it can be expressed in the form x=a1b1abx = a^{-1}b^{-1}ab for some a,bGa, b \in G. In 2010 MacHale posed the following problem in the Kourovka notebook: does there exist a finite group GG, with G>2|G| > 2, such that there is exactly one element of GG which is not a commutator? We answer this question in the affirmative and provide an infinite series of such groups, the smallest group in our construction having size 1660944384016609443840.

Keywords

Cite

@article{arxiv.2509.17587,
  title  = {On finite groups with exactly one noncommutator},
  author = {Saveliy V. Skresanov},
  journal= {arXiv preprint arXiv:2509.17587},
  year   = {2025}
}

Comments

4 pages. GAP code in the ancillary file

R2 v1 2026-07-01T05:49:15.006Z