{"title":"Classification of cyclic groups underlying only smooth skew morphisms","authors":"","doi":"10.1007/s10801-024-01311-4","DOIUrl":null,"url":null,"abstract":"<h3>Abstract</h3> <p>A skew morphism of a finite group <em>A</em> is a permutation <span> <span>\\(\\varphi \\)</span> </span> of <em>A</em> fixing the identity element and for which there is an integer-valued function <span> <span>\\(\\pi \\)</span> </span> on <em>A</em> such that <span> <span>\\(\\varphi (ab)=\\varphi (a)\\varphi ^{\\pi (a)}(b)\\)</span> </span> for all <span> <span>\\(a, b \\in A\\)</span> </span>. A skew morphism <span> <span>\\(\\varphi \\)</span> </span> of <em>A</em> is smooth if the associated power function <span> <span>\\(\\pi \\)</span> </span> is constant on the orbits of <span> <span>\\(\\varphi \\)</span> </span>, that is, <span> <span>\\(\\pi (\\varphi (a))\\equiv \\pi (a)\\pmod {|\\varphi |}\\)</span> </span> for all <span> <span>\\(a\\in A\\)</span> </span>. In this paper, we show that every skew morphism of a cyclic group of order <em>n</em> is smooth if and only if <span> <span>\\(n=2^en_1\\)</span> </span>, where <span> <span>\\(0 \\le e \\le 4\\)</span> </span> and <span> <span>\\(n_1\\)</span> </span> is an odd square-free number. A partial solution to a similar problem on non-cyclic abelian groups is also given.</p>","PeriodicalId":0,"journal":{"name":"","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"","FirstCategoryId":"100","ListUrlMain":"https://doi.org/10.1007/s10801-024-01311-4","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
引用次数: 0
Abstract
A skew morphism of a finite group A is a permutation \(\varphi \) of A fixing the identity element and for which there is an integer-valued function \(\pi \) on A such that \(\varphi (ab)=\varphi (a)\varphi ^{\pi (a)}(b)\) for all \(a, b \in A\). A skew morphism \(\varphi \) of A is smooth if the associated power function \(\pi \) is constant on the orbits of \(\varphi \), that is, \(\pi (\varphi (a))\equiv \pi (a)\pmod {|\varphi |}\) for all \(a\in A\). In this paper, we show that every skew morphism of a cyclic group of order n is smooth if and only if \(n=2^en_1\), where \(0 \le e \le 4\) and \(n_1\) is an odd square-free number. A partial solution to a similar problem on non-cyclic abelian groups is also given.