{ "id": "2212.14525", "version": "v1", "published": "2022-12-30T02:59:31.000Z", "updated": "2022-12-30T02:59:31.000Z", "title": "Maxima of the $Q$-index of non-bipartite graphs: forbidden short odd cycles", "authors": [ "Lu Miao", "Ruifang Liu", "Jie Xue" ], "comment": "15 pages, 5 figures. arXiv admin note: text overlap with arXiv:2209.00801", "categories": [ "math.CO" ], "abstract": "Let $G$ be a non-bipartite graph which does not contain any odd cycle of length at most $2k+1$. In this paper, we determine the maximum $Q$-index of $G$ if its order is fixed, and the corresponding extremal graph is uniquely characterized. Moreover, if the size of $G$ is given, the maximum $Q$-index of $G$ and the unique extremal graph are also proved.", "revisions": [ { "version": "v1", "updated": "2022-12-30T02:59:31.000Z" } ], "analyses": { "subjects": [ "05C50", "05C35" ], "keywords": [ "forbidden short odd cycles", "non-bipartite graph", "unique extremal graph", "corresponding extremal graph" ], "note": { "typesetting": "TeX", "pages": 15, "language": "en", "license": "arXiv", "status": "editable" } } }