{ "id": "2206.13490", "version": "v1", "published": "2022-06-27T17:52:33.000Z", "updated": "2022-06-27T17:52:33.000Z", "title": "A Critical Probability for Biclique Partition of $G_{n,p}$", "authors": [ "Tom Bohman", "Jakob Hofstad" ], "categories": [ "math.CO" ], "abstract": "The biclique partition number of a graph $G= (V,E)$, denoted $bp(G)$, is the minimum number of pairwise edge disjoint complete bipartite subgraphs of $G$ so that each edge of $G$ belongs to exactly one of them. It is easy to see that $ bp(G) \\leq n - \\alpha(G)$, where $\\alpha(G)$ is the maximum size of an independent set of $G$. Erd\\H{o}s conjectured in the 80's that for almost every graph $G$ equality holds; i.e., if $ G=G_{n,1/2}$ then $bp(G) = n - \\alpha(G)$ with high probability. Alon showed that this is false. We show that the conjecture of Erd\\H{o}s is true if we instead take $ G=G_{n,p}$, where $p$ is constant and less than a certain threshold value $p_0 \\approx 0.312$. This verifies a conjecture of Chung and Peng for these values of $p$. We also show that, if $p_0 \\leq p <1/2$, then $bp(G_{n,p}) = n - (1 + \\Theta(1)) \\alpha(G_{n,p})$ with high probability.", "revisions": [ { "version": "v1", "updated": "2022-06-27T17:52:33.000Z" } ], "analyses": { "subjects": [ "05C80", "05C69", "05C70" ], "keywords": [ "critical probability", "edge disjoint complete bipartite subgraphs", "pairwise edge disjoint complete bipartite", "high probability", "biclique partition number" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }