{ "id": "math/0406542", "version": "v2", "published": "2004-06-26T16:47:26.000Z", "updated": "2005-03-17T18:39:53.000Z", "title": "Distinguishing numbers for graphs and groups", "authors": [ "Julianna S. Tymoczko" ], "comment": "13 pages; final version", "journal": "Electronic Journal of Combinatorics, 11 (1) (2004), #R63", "categories": [ "math.CO", "math.GR" ], "abstract": "A graph G is distinguished if its vertices are labelled by a map \\phi: V(G) \\longrightarrow {1,2,...,k} so that no graph automorphism preserves \\phi. The distinguishing number of G is the minimum number k necessary for \\phi to distinguish the graph. It is one measure of the complexity of the graph. We extend these definitions to an arbitrary group action of G on a set X. A labelling \\phi: X \\longrightarrow {1,2,...,k} is distinguishing if no nontrivial element of G preserves \\phi except those in the stabilizer of X. The distinguishing number of the group action on X is the minimum k needed for \\phi to distinguish the group action. We show that distinguishing group actions is a more general problem than distinguishing graphs. We completely characterize actions of the symmetric group S_n on a set with distinguishing number n.", "revisions": [ { "version": "v2", "updated": "2005-03-17T18:39:53.000Z" } ], "analyses": { "subjects": [ "05C15", "05C25", "20D60" ], "keywords": [ "distinguishing number", "graph automorphism preserves", "arbitrary group action", "minimum number", "nontrivial element" ], "tags": [ "journal article" ], "note": { "typesetting": "TeX", "pages": 13, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2004math......6542T" } } }