{ "id": "1412.4058", "version": "v1", "published": "2014-12-12T17:12:06.000Z", "updated": "2014-12-12T17:12:06.000Z", "title": "The $h$-critical number of finite abelian groups", "authors": [ "Bela Bajnok" ], "categories": [ "math.NT" ], "abstract": "For a finite abelian group $G$ and a positive integer $h$, the unrestricted (resp.~restricted) $h$-critical number $\\chi(G,h)$ (resp.~$\\chi \\hat{\\;}(G,h)$) of $G$ is defined to be the minimum value of $m$, if exists, for which the $h$-fold unrestricted (resp.~restricted) sumset of every $m$-subset of $G$ equals $G$ itself. Here we determine $\\chi(G,h)$ for all $G$ and $h$; and prove several results for $\\chi \\hat{\\;}(G,h)$, including the cases of any $G$ and $h = 2$, any $G$ and large $h$, and any $h$ for the cyclic group $\\mathbb{Z}_n$ of even order. We also provide a lower bound for $\\chi \\hat{\\;}(\\mathbb{Z}_n,3)$ that we believe is exact for every $n$---this conjecture is a generalization of the one made by Gallardo, Grekos, et al.~that was proved (for large $n$) by Lev.", "revisions": [ { "version": "v1", "updated": "2014-12-12T17:12:06.000Z" } ], "analyses": { "keywords": [ "finite abelian group", "critical number", "minimum value", "cyclic group", "lower bound" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2014arXiv1412.4058B" } } }