{ "id": "1610.07836", "version": "v1", "published": "2016-10-25T11:34:31.000Z", "updated": "2016-10-25T11:34:31.000Z", "title": "Classification of crescent configurations", "authors": [ "Rebecca F. Durst", "Max Hlavacek", "Chi Huynh", "Steven J. Miller", "Eyvindur A. Palsson" ], "comment": "23 pages", "categories": [ "math.CO" ], "abstract": "Let $n$ points be in crescent configurations in $\\mathbb{R}^d$ if they lie in general position in $\\mathbb{R}^d$ and determine $n-1$ distinct distances, such that for every $1 \\leq i \\leq n-1$ there is a distance that occurs exactly $i$ times. Since Erd\\H{o}s' conjecture in 1989 on the existence of $N$ sufficiently large such that no crescent configurations exist on $N$ or more points, he, Pomerance, and Pal\\'asti have given constructions for $n$ up to $8$ but nothing is yet known for $n \\geq 9$. Most recently, Burt et. al. had proven that a crescent configuration on $n$ points exists in $\\mathbb{R}^{n-2}$ for $n \\geq 3$. In this paper, we study the classification of these configurations on $4$ and $5$ points through graph isomorphism and rigidity. Our techniques, which can be generalized to higher dimensions, offer a new viewpoint on the problem through the lens of distance geometry and provide a systematic way to construct crescent configurations.", "revisions": [ { "version": "v1", "updated": "2016-10-25T11:34:31.000Z" } ], "analyses": { "keywords": [ "classification", "construct crescent configurations", "distinct distances", "general position", "graph isomorphism" ], "note": { "typesetting": "TeX", "pages": 23, "language": "en", "license": "arXiv", "status": "editable" } } }