{ "id": "2105.02361", "version": "v1", "published": "2021-05-05T22:44:50.000Z", "updated": "2021-05-05T22:44:50.000Z", "title": "The ratio of the numbers of odd and even cycles in outerplanar graphs", "authors": [ "Akihiro Higashitani", "Naoki Matsumoto" ], "comment": "16 page, 10 figures", "categories": [ "math.CO", "cs.DM" ], "abstract": "In this paper, we investigate the ratio of the numbers of odd and even cycles in outerplanar graphs. We verify that the ratio generally diverges to infinity as the order of a graph diverges to infinity. We also give sharp estimations of the ratio for several classes of outerplanar graphs, and obtain a constant upper bound of the ratio for some of them. Furthermore, we consider similar problems in graphs with some pairs of forbidden subgraphs/minors, and propose a challenging problem concerning claw-free graphs.", "revisions": [ { "version": "v1", "updated": "2021-05-05T22:44:50.000Z" } ], "analyses": { "subjects": [ "05C30", "05C31", "G.2" ], "keywords": [ "outerplanar graphs", "constant upper bound", "challenging problem concerning claw-free graphs", "similar problems", "forbidden subgraphs/minors" ], "note": { "typesetting": "TeX", "pages": 16, "language": "en", "license": "arXiv", "status": "editable" } } }