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arXiv · 2001.01566

Bi-Skew Braces and Regular Subgroups of the Holomorph

A. Caranti
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Abstract

L. Childs has defined a skew brace $(G, \cdot, \circ)$ to be a bi-skew brace if $(G, \circ, \cdot)$ is also a skew brace, and has given applications of this concept to the equivalent theory of Hopf-Galois structures. The goal of this paper is to deal with bi-skew braces $(G, \cdot, \circ)$ from the yet equivalent point of view of regular subgroups of the holomorph of $(G, \cdot)$. In particular, we find that certain groups studied by T. Kohl, F. Dalla Volta and the author, and C. Tsang all yield examples of bi-skew braces. Building on a construction of Childs, we also give various methods for constructing further examples of bi-skew braces.

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A. Caranti. 2020-07-22. Bi-Skew Braces and Regular Subgroups of the Holomorph. https://doi.org/10.1016/j.jalgebra.2020.07.006

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