{ "id": "1612.07888", "version": "v1", "published": "2016-12-23T07:14:34.000Z", "updated": "2016-12-23T07:14:34.000Z", "title": "On the genus of the complete tripartite graph $K_{n,n,1}$", "authors": [ "Valentas Kurauskas" ], "comment": "15 pages, 6 figures", "journal": "Discrete Math, 340 (2017), 508-515", "doi": "10.1016/j.disc.2016.09.017", "categories": [ "math.CO" ], "abstract": "For even $n$ we prove that the genus of the complete tripartite graph $K_{n,n,1}$ is $\\lceil (n-1) (n-2)/4 \\rceil$. This is the least number of bridges needed to build a complete $n$-way road interchange where changing lanes is not allowed. Both the theoretical result, and the surprising link to modelling road intersections are new.", "revisions": [ { "version": "v1", "updated": "2016-12-23T07:14:34.000Z" } ], "analyses": { "keywords": [ "complete tripartite graph", "way road interchange", "modelling road intersections", "changing lanes", "theoretical result" ], "tags": [ "journal article" ], "publication": { "publisher": "Elsevier" }, "note": { "typesetting": "TeX", "pages": 15, "language": "en", "license": "arXiv", "status": "editable" } } }