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arXiv · 1912.12013

Skew-morphisms of nonabelian characteristically simple groups

Jiyong Chen·Shaofei Du·Cai Heng Li
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Abstract

A skew-morphism of a finite group $G$ is a permutation $\s$ on $G$ fixing the identity element, and for which there exists an integer function $\pi$ on $G$ such that $\s(xy)=\s(x)\s^{\pi(x)}(y)$ for all $x,y\in G$. It has been known that given a skew-morphism $\s $ of $G$, the product of $\lg \s \rg$ with the left regular representation of $G$ forms a permutation group on $G$, called the skew-product group of $\s$. The skew-morphism was introduced as an algebraic tool to investigate regular Cayley maps. In this paper, the skew-product groups are characterized, for all skew-morphisms of finite nonabelian characteristically simple groups (see Theorem 1.1) and correspondingly the Cayley maps on these groups are characterized (see Theorem 1.5).

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Jiyong Chen, Shaofei Du, Cai Heng Li. 2019-12-27. Skew-morphisms of nonabelian characteristically simple groups. https://arxiv.org/abs/1912.12013

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