{ "id": "1904.05307", "version": "v1", "published": "2019-04-10T17:17:20.000Z", "updated": "2019-04-10T17:17:20.000Z", "title": "On the sizes of large subgraphs of the binomial random graph", "authors": [ "Jozsef Balogh", "Maksim Zhukovskii" ], "categories": [ "math.CO" ], "abstract": "In the paper, we answer the following two questions. Given $e(k)=p{k\\choose 2}+O(k)$, what is the maximum $k$ such that $G(n,p)$ has an induced subgraph with $k$ vertices and $e(k)$ edges? Given $k>\\varepsilon n$, what is the maximum $\\mu$ such that a.a.s.~the set of sizes of $k$-vertex subgraphs of $G(n,p)$ contains a full interval of length $\\mu$? We prove that the value $\\mathcal{X}_n$ from the first question is not concentrated in any finite set (in contrast to the case of a small $e=e(k)$). Moreover, we prove that for an $\\omega_n\\to\\infty$, a.a.s.~the size of the concentration set is smaller than $\\omega_n\\sqrt{n/\\ln n}$. Otherwise, for an arbitrary constant $C>0$, a.a.s.~it is bigger than $C\\sqrt{n/\\ln n}$. Our answer on the second question is the following: $\\mu=\\Theta(\\sqrt{(n-k)n\\ln{n\\choose k}})$.", "revisions": [ { "version": "v1", "updated": "2019-04-10T17:17:20.000Z" } ], "analyses": { "keywords": [ "binomial random graph", "large subgraphs", "second question", "arbitrary constant", "vertex subgraphs" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }