English

Constructing Hopf-Galois structures and skew bracoids of small degree

Group Theory 2026-04-06 v2

Abstract

Using the fact that Hopf-Galois structures on separable extensions and skew bracoids are both intrinsically connected to transitive subgroups of the holomorph of a finite group, we present algorithms to classify and enumerate these objects for small degree, and apply them to obtain significant extensions to existing results. We also explore the classifications of these structures of degree 2pq2pq, where pp and qq are distinct odd primes. We conclude with some enumeration-inspired observations and a conjecture.

Keywords

Cite

@article{arxiv.2508.03372,
  title  = {Constructing Hopf-Galois structures and skew bracoids of small degree},
  author = {Andrew Darlington and Eamonn O'Brien},
  journal= {arXiv preprint arXiv:2508.03372},
  year   = {2026}
}

Comments

Major revision, 23 pages. Significant portions of the paper have been rewritten and computational results have been greatly extended