{ "id": "1911.11406", "version": "v1", "published": "2019-11-26T08:49:55.000Z", "updated": "2019-11-26T08:49:55.000Z", "title": "On Gorenstein Graphs with Independence Number at Most Three", "authors": [ "Mohammad Reza Oboudi", "Ashkan Nikseresht" ], "comment": "10 pages", "categories": [ "math.CO" ], "abstract": "Suppose that $G$ is a simple graph on $n$ vertices and $\\alpha=\\alpha(G)$ is the independence number of $G$. Let $I(G)$ be the edge ideal of $G$ in $S=K[x_1, \\ldots, x_n]$. We say that $G$ is Gorenstein when $S/I(G)$ is so. Here, first we present a condition on $G$ equivalent to $G$ being Gorenstein and use this to get a full characterization of Gorenstein graphs with $\\alpha=2$. Then we focus on Gorenstein graphs with $\\alpha=3$ and find the number of edges and the independence polynomial of such graphs. Finally, we present a full characterization of triangle-free Gorenstein graphs with $\\alpha=3$.", "revisions": [ { "version": "v1", "updated": "2019-11-26T08:49:55.000Z" } ], "analyses": { "subjects": [ "13F55", "05E40", "13H10" ], "keywords": [ "independence number", "full characterization", "triangle-free gorenstein graphs", "simple graph", "edge ideal" ], "note": { "typesetting": "TeX", "pages": 10, "language": "en", "license": "arXiv", "status": "editable" } } }