{ "id": "1810.05266", "version": "v1", "published": "2018-10-11T21:43:53.000Z", "updated": "2018-10-11T21:43:53.000Z", "title": "Optimal pebbling number of the square grid", "authors": [ "Ervin Győri", "Gyula Y. Katona", "László F. Papp" ], "categories": [ "math.CO" ], "abstract": "A pebbling move on a graph removes two pebbles from a vertex and adds one pebble to an adjacent vertex. A vertex is reachable from a pebble distribution if it is possible to move a pebble to that vertex using pebbling moves. The optimal pebbling number $\\pi_{opt}$ is the smallest number m needed to guarantee a pebble distribution of m pebbles from which any vertex is reachable. The optimal pebbling number of the square grid graph $P_n\\square P_m$ was investigated in several papers. In this paper, we present a new method using some recent ideas to give a lower bound on $\\pi_{opt}$. We apply this technique to prove that $\\pi_{opt}(P_n\\square P_m)\\geq \\frac{2}{13}nm$. Our method also gives a new proof for $\\pi_{opt}(P_n)=\\pi_{opt}(C_n)=\\left\\lceil\\frac{2n}{3}\\right\\rceil$.", "revisions": [ { "version": "v1", "updated": "2018-10-11T21:43:53.000Z" } ], "analyses": { "keywords": [ "optimal pebbling number", "pebbling move", "pebble distribution", "square grid graph", "graph removes" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }