{ "id": "1804.03717", "version": "v1", "published": "2018-04-10T21:00:52.000Z", "updated": "2018-04-10T21:00:52.000Z", "title": "Optimal pebbling number of graphs with given minimum degree", "authors": [ "Andrzej Czygrinow", "Glenn Hurlbert", "Gyula Y. Katona", "László F. Papp" ], "categories": [ "math.CO" ], "abstract": "Consider a distribution of pebbles on a connected graph $G$. A pebbling move removes two pebbles from a vertex and places one to an adjacent vertex. A vertex is reachable under a pebbling distribution if it has a pebble after the application of a sequence of pebbling moves. The optimal pebbling number $\\pi^*(G)$ is the smallest number of pebbles which we can distribute in such a way that each vertex is reachable. It was known that the optimal pebbling number of any connected graph is at most $\\frac{4n}{\\delta+1}$, where $\\delta$ is the minimum degree of the graph. We strengthen this bound by showing that equality cannot be attained and that the bound is sharp. If $\\operatorname{diam}(G)\\geq 3$ then we further improve the bound to $\\pi^*(G)\\leq\\frac{3.75n}{\\delta+1}$. On the other hand, we show that for arbitrary large diameter and any $\\epsilon>0$ there are infinitely many graphs whose optimal pebbling number is bigger than $\\left(\\frac{8}{3}-\\epsilon\\right)\\frac{n}{(\\delta+1)}$.", "revisions": [ { "version": "v1", "updated": "2018-04-10T21:00:52.000Z" } ], "analyses": { "keywords": [ "optimal pebbling number", "minimum degree", "connected graph", "arbitrary large diameter", "distribution" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }