{ "id": "math/0403219", "version": "v1", "published": "2004-03-13T04:50:59.000Z", "updated": "2004-03-13T04:50:59.000Z", "title": "On the sandpile group of regular trees", "authors": [ "Evelin Toumpakari" ], "comment": "24 pages", "categories": [ "math.CO" ], "abstract": "The sandpile group of a connected graph is the group of recurrent configurations in the abelian sandpile model on this graph. We study the structure of this group for the case of regular trees. A description of this group is the following: Let T(d,h) be the d-regular tree of depth h and let V be the set of its vertices. Denote the adjacency matrix of T(d,h) by A and consider the modified Laplacian matrix D:=dI-A. Let the rows of D span the lattice L in Z^V. The sandpile group of T(d,h) is Z^V/L. We compute the rank, the exponent and the order of this abelian group and find a cyclic Hall-subgroup of order (d-1)^h. We find that the base (d-1)-logarithm of the exponent and of the order are asymptotically 3h^2/pi^2 and c_d(d-1)^h, respectively. We conjecture an explicit formula for the ranks of all Sylow subgroups.", "revisions": [ { "version": "v1", "updated": "2004-03-13T04:50:59.000Z" } ], "analyses": { "subjects": [ "05C50", "05C25", "20K01", "82B20" ], "keywords": [ "sandpile group", "regular trees", "abelian sandpile model", "d-regular tree", "sylow subgroups" ], "note": { "typesetting": "TeX", "pages": 24, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2004math......3219T" } } }