{ "id": "1807.09086", "version": "v1", "published": "2018-07-24T13:19:14.000Z", "updated": "2018-07-24T13:19:14.000Z", "title": "The Möbius function of ${\\rm PSU}(3,2^{2^n})$", "authors": [ "Giovanni Zini" ], "categories": [ "math.CO" ], "abstract": "Let $G$ be the simple group ${\\rm PSU}(2,2^{2^n})$, $n>0$. For any subgroup $H$ of $G$, we compute the M\\\"obius function $\\mu_L(H,G)$ of $H$ in the subgroup lattice $L$ of $G$, and the M\\\"obius function $\\mu_{\\bar L}([H],[G])$ of $[H]$ in the poset $\\bar L$ of conjugacy classes of subgroups of $G$. For any prime $p$, we provide the Euler characteristic of the order complex of the poset of $p$-subgroups of $G$.", "revisions": [ { "version": "v1", "updated": "2018-07-24T13:19:14.000Z" } ], "analyses": { "subjects": [ "20D30" ], "keywords": [ "möbius function", "simple group", "subgroup lattice", "conjugacy classes" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }