{ "id": "2102.06993", "version": "v1", "published": "2021-02-13T19:52:06.000Z", "updated": "2021-02-13T19:52:06.000Z", "title": "The choice number versus the chromatic number for graphs embeddable on orientable surfaces", "authors": [ "Niranjan Balachandran", "Brahadeesh Sankarnarayanan" ], "comment": "17 pages, 6 figures", "categories": [ "math.CO" ], "abstract": "We show that for loopless $6$-regular triangulations on the torus the gap between the choice number and chromatic number is at most $2$. We also show that the largest gap for graphs embeddable in an orientable surface of genus $g$ is of the order $\\Theta(\\sqrt{g})$, and moreover for graphs with chromatic number of the order $o(\\sqrt{g}/\\log(g))$ the largest gap is of the order $o(\\sqrt{g})$.", "revisions": [ { "version": "v1", "updated": "2021-02-13T19:52:06.000Z" } ], "analyses": { "subjects": [ "05C15", "05C10", "05C35", "05C75" ], "keywords": [ "chromatic number", "choice number", "orientable surface", "graphs embeddable" ], "note": { "typesetting": "TeX", "pages": 17, "language": "en", "license": "arXiv", "status": "editable" } } }