{ "id": "2008.09291", "version": "v1", "published": "2020-08-21T03:38:08.000Z", "updated": "2020-08-21T03:38:08.000Z", "title": "The non-commuting, non-generating graph of a nilpotent group", "authors": [ "Peter J. Cameron", "Saul D. Freedman", "Colva M. Roney-Dougal" ], "comment": "13 pages", "categories": [ "math.GR" ], "abstract": "For a nilpotent group $G$, let $\\Xi(G)$ be the difference between the complement of the generating graph of $G$ and the commuting graph of $G$, with vertices corresponding to central elements of $G$ removed. That is, $\\Xi(G)$ has vertex set $G \\setminus Z(G)$, with two vertices adjacent if and only if they do not commute and do not generate $G$. Additionally, let $\\Xi^+(G)$ be the subgraph of $\\Xi(G)$ induced by its non-isolated vertices. We show that if $\\Xi(G)$ has an edge, then $\\Xi^+(G)$ is connected with diameter $2$ or $3$, with $\\Xi(G) = \\Xi^+(G)$ in the diameter $3$ case. In the infinite case, our results apply more generally, to any group with every maximal subgroup normal. When $G$ is finite, we explore the relationship between the structures of $G$ and $\\Xi(G)$ in more detail.", "revisions": [ { "version": "v1", "updated": "2020-08-21T03:38:08.000Z" } ], "analyses": { "subjects": [ "20F18", "05C25" ], "keywords": [ "nilpotent group", "non-generating graph", "maximal subgroup normal", "vertex set", "central elements" ], "note": { "typesetting": "TeX", "pages": 13, "language": "en", "license": "arXiv", "status": "editable" } } }