English

Aperiodic Pointlikes and Beyond

Group Theory 2007-06-17 v2

Abstract

We prove that if π\pi is a recursive set of primes, then pointlike sets are decidable for the pseudovariety of semigroups whose subgroups are π\pi-groups. In particular, when π\pi is the empty set, we obtain Henckell's decidability of aperiodic pointlikes. Our proof, restricted to the case of aperiodic semigroups, is simpler than the original proof.

Keywords

Cite

@article{arxiv.0706.0248,
  title  = {Aperiodic Pointlikes and Beyond},
  author = {Karsten Henckell and John Rhodes and Benjamin Steinberg},
  journal= {arXiv preprint arXiv:0706.0248},
  year   = {2007}
}
R2 v1 2026-06-21T08:34:29.836Z