{ "id": "2203.02362", "version": "v1", "published": "2022-03-04T14:55:50.000Z", "updated": "2022-03-04T14:55:50.000Z", "title": "Classification of non-solvable groups whose power graph is a cograph", "authors": [ "Jendrik Brachter", "Eda Kaja" ], "categories": [ "math.GR", "math.CO" ], "abstract": "Cameron, Manna and Mehatari investigated the question of which finite groups admit a power graph that is a cograph, also called power-cograph groups (Journal of Algebra 591 (2022)). They give a classification for nilpotent groups and partial results for general groups. However, the authors point out number theoretic obstacles towards a classification. These arise when the groups are assumed to be isomorphic to PSL 2 (q) or Sz(q) and are likely to be hard. In this paper, we prove that these number theoretic problems are in fact the only obstacles to the classification of non-solvable power-cograph groups. Specifically, for the non-solvable case, we give a classification of power-cograph groups in terms of such groups isomorphic to PSL 2 (q) or Sz(q). For the solvable case, we are able to precisely describe the structure of solvable power-cograph groups. We obtain a complete classification of solvable power-cograph groups whose Gruenberg-Kegel graph is connected. Moreover, we reduce the case where the Gruenberg-Kegel graph is disconnected to the classification of p-groups admitting fixed-point-free automorphisms of prime power order, which is in general an open problem.", "revisions": [ { "version": "v1", "updated": "2022-03-04T14:55:50.000Z" } ], "analyses": { "subjects": [ "20E34", "05C25" ], "keywords": [ "classification", "power graph", "non-solvable groups", "solvable power-cograph groups", "gruenberg-kegel graph" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }