{ "id": "1510.03950", "version": "v1", "published": "2015-10-14T02:33:08.000Z", "updated": "2015-10-14T02:33:08.000Z", "title": "On the Ramsey-Turán number with small $s$-independence number", "authors": [ "Patrick Bennett", "Andrzej Dudek" ], "comment": "24 pp", "categories": [ "math.CO" ], "abstract": "Let $s$ be an integer, $f=f(n)$ a function, and $H$ a graph. Define the Ramsey-Tur\\'an number $RT_s(n,H, f)$ as the maximum number of edges in an $H$-free graph $G$ of order $n$ with $\\alpha_s(G) < f$, where $\\alpha_s(G)$ is the maximum number of vertices in a $K_s$-free induced subgraph of $G$. The Ramsey-Tur\\'an number attracted a considerable amount of attention and has been mainly studied for $f$ not too much smaller than $n$. In this paper we consider $RT_s(n,K_t, n^{\\delta})$ for fixed $\\delta<1$. We show that for an arbitrarily small $\\varepsilon>0$ and $1/2<\\delta< 1$, $RT_s(n,K_{s+1}, n^{\\delta}) = \\Omega(n^{1+\\delta-\\varepsilon})$ for all sufficiently large $s$. This is nearly optimal, since a trivial upper bound yields $RT_s(n,K_{s+1}, n^{\\delta}) = O(n^{1+\\delta})$. Furthermore, the range of $\\delta$ is as large as possible. We also consider more general cases and find bounds on $RT_s(n,K_{s+r},n^{\\delta})$ for fixed $r\\ge2$. Finally, we discuss some \"jumping\" behavior of $RT_s(n, K_{2s}, n^\\delta)$ and $RT_s(n, K_{2s+1}, n^\\delta)$.", "revisions": [ { "version": "v1", "updated": "2015-10-14T02:33:08.000Z" } ], "analyses": { "keywords": [ "independence number", "ramsey-turán number", "maximum number", "ramsey-turan number", "trivial upper bound yields" ], "note": { "typesetting": "TeX", "pages": 24, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2015arXiv151003950B" } } }