{ "id": "2006.11104", "version": "v1", "published": "2020-06-19T12:40:26.000Z", "updated": "2020-06-19T12:40:26.000Z", "title": "On subgroup perfect codes in Cayley graphs", "authors": [ "Junyang Zhang", "Sanming Zhou" ], "comment": "Final version, European Journal of Combinatorics, to appear", "categories": [ "math.CO" ], "abstract": "A perfect code in a graph $\\Gamma = (V, E)$ is a subset $C$ of $V$ such that no two vertices in $C$ are adjacent and every vertex in $V \\setminus C$ is adjacent to exactly one vertex in $C$. A subgroup $H$ of a group $G$ is called a subgroup perfect code of $G$ if there exists a Cayley graph of $G$ which admits $H$ as a perfect code. Equivalently, $H$ is a subgroup perfect code of $G$ if there exists an inverse-closed subset $A$ of $G$ containing the identity element such that $(A, H)$ is a tiling of $G$ in the sense that every element of $G$ can be uniquely expressed as the product of an element of $A$ and an element of $H$. In this paper we obtain multiple results on subgroup perfect codes of finite groups, including a few necessary and sufficient conditions for a subgroup of a finite group to be a subgroup perfect code, a few results involving $2$-subgroups in the study of subgroup perfect codes, and several results on subgroup perfect codes of metabelian groups, generalized dihedral groups, nilpotent groups and $2$-groups.", "revisions": [ { "version": "v1", "updated": "2020-06-19T12:40:26.000Z" } ], "analyses": { "subjects": [ "05C25", "05C69", "94B25" ], "keywords": [ "subgroup perfect code", "cayley graph", "finite group", "generalized dihedral groups", "metabelian groups" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }