{ "id": "2207.04641", "version": "v1", "published": "2022-07-11T05:50:35.000Z", "updated": "2022-07-11T05:50:35.000Z", "title": "The complement of enhanced power graph of a finite group", "authors": [ "Parveen", "Jitender Kumar" ], "comment": "7 figures", "categories": [ "math.GR", "math.CO" ], "abstract": "The enhanced power graph $\\mathcal{P}_E(G)$ of a finite group $G$ is the simple undirected graph whose vertex set is $G$ and two distinct vertices $x, y$ are adjacent if $x, y \\in \\langle z \\rangle$ for some $z \\in G$. In this article, we give an affirmative answer of the question posed by Cameron [6] which states that: Is it true that the complement of the enhanced power graph $\\bar{\\mathcal{P}_E(G)}$ of a non-cyclic group $G$ has only one connected component apart from isolated vertices? We classify all finite groups $G$ such that the graph $\\bar{\\mathcal{P}_E(G)}$ is bipartite. We show that the graph $\\bar{\\mathcal{P}_E(G)}$ is weakly perfect. Further, we study the subgraph $\\bar{\\mathcal{P}_E(G^*)}$ of $\\bar{\\mathcal{P}_E(G)}$ induced by all the non-isolated vertices of $\\bar{\\mathcal{P}_E(G)}$. We classify all finite groups $G$ such that the graph is $\\bar{\\mathcal{P}_E(G^*)}$ is unicyclic and pentacyclic. We prove the non-existence of finite groups $G$ such that the graph $\\bar{\\mathcal{P}_E(G^*)}$ is bicyclic, tricyclic or tetracyclic. Finally, we characterize all finite groups $G$ such that the graph $\\bar{\\mathcal{P}_E(G^*)}$ is outerplanar, planar, projective-planar and toroidal, respectively.", "revisions": [ { "version": "v1", "updated": "2022-07-11T05:50:35.000Z" } ], "analyses": { "subjects": [ "05C25" ], "keywords": [ "finite group", "enhanced power graph", "complement", "vertex set", "distinct vertices" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }