{ "id": "1508.07485", "version": "v1", "published": "2015-08-29T17:47:35.000Z", "updated": "2015-08-29T17:47:35.000Z", "title": "On zero-sum $\\mathbb{Z}_{2j}^k$-magic graphs", "authors": [ "J. P. Georges", "D. Mauro", "K. Wash" ], "categories": [ "math.CO" ], "abstract": "Let $G = (V,E)$ be a finite graph and let $(\\mathbb{A},+)$ be an abelian group with identity 0. Then $G$ is \\textit{$\\mathbb{A}$-magic} if and only if there exists a function $\\phi$ from $E$ into $\\mathbb{A} - \\{0\\}$ such that for some $c \\in \\mathbb{A}$, $\\sum_{e \\in E(v)} \\phi(e) = c$ for every $v \\in V$, where $E(v)$ is the set of edges incident to $v$. Additionally, $G$ is \\textit{zero-sum $\\mathbb{A}$-magic} if and only if $\\phi$ exists such that $c = 0$. We consider zero-sum $\\mathbb{A}$-magic labelings of graphs, with particular attention given to $\\mathbb{A} = \\mathbb{Z}_{2j}^k$. For $j \\geq 1$, let $\\zeta_{2j}(G)$ be the smallest positive integer $c$ such that $G$ is zero-sum $\\mathbb{Z}_{2j}^c$-magic if $c$ exists; infinity otherwise. We establish upper bounds on $\\zeta_{2j}(G)$ when $\\zeta_{2j}(G)$ is finite, and show that $\\zeta_{2j}(G)$ is finite for all $r$-regular $G$, $r \\geq 2$. Appealing to classical results on the factors of cubic graphs, we prove that $\\zeta_4(G) \\leq 2$ for a cubic graph $G$, with equality if and only if $G$ has no 1-factor. We discuss the problem of classifying cubic graphs according to the collection of finite abelian groups for which they are zero-sum group-magic.", "revisions": [ { "version": "v1", "updated": "2015-08-29T17:47:35.000Z" } ], "analyses": { "subjects": [ "05C78" ], "keywords": [ "magic graphs", "finite abelian groups", "magic labelings", "zero-sum group-magic", "establish upper bounds" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }