{ "id": "2306.09089", "version": "v1", "published": "2023-06-15T12:40:01.000Z", "updated": "2023-06-15T12:40:01.000Z", "title": "Mostar index and bounded maximum degree", "authors": [ "Michael A. Henning", "Johannes Pardey", "Dieter Rautenbach", "Florian Werner" ], "categories": [ "math.CO" ], "abstract": "Do\\v{s}li\\'{c} et al. defined the Mostar index of a graph $G$ as $Mo(G)=\\sum\\limits_{uv\\in E(G)}|n_G(u,v)-n_G(v,u)|$, where, for an edge $uv$ of $G$, the term $n_G(u,v)$ denotes the number of vertices of $G$ that have a smaller distance in $G$ to $u$ than to $v$. For a graph $G$ of order $n$ and maximum degree at most $\\Delta$, we show $Mo(G)\\leq \\frac{\\Delta}{2}n^2-(1-o(1))c_{\\Delta}n\\log(\\log(n)),$ where $c_{\\Delta}>0$ only depends on $\\Delta$ and the $o(1)$ term only depends on $n$. Furthermore, for integers $n_0$ and $\\Delta$ at least $3$, we show the existence of a $\\Delta$-regular graph of order $n$ at least $n_0$ with $Mo(G)\\geq \\frac{\\Delta}{2}n^2-c'_{\\Delta}n\\log(n),$ where $c'_{\\Delta}>0$ only depends on $\\Delta$.", "revisions": [ { "version": "v1", "updated": "2023-06-15T12:40:01.000Z" } ], "analyses": { "keywords": [ "bounded maximum degree", "mostar index", "regular graph", "smaller distance" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }