On Turán exponents of bipartite graphs
نویسندگان
چکیده
Abstract A long-standing conjecture of Erd?s and Simonovits asserts that for every rational number $r\in (1,2)$ there exists a bipartite graph H such $\mathrm{ex}(n,H)=\Theta(n^r)$ . So far this is known to be true only rationals form $1+1/k$ $2-1/k$ , integers $k\geq 2$ In paper, we add new which the true: $2-2/(2k+1)$ This in turn also gives an affirmative answer question Pinchasi Sharir on cube-like graphs. Recently, version $^{\prime}$ s conjecture, where one replaces single by finite family, was confirmed Bukh Conlon. They proposed construction graphs should satisfy conjecture. Our result can viewed as first step towards verifying Conlon We prove upper bound Turán theta asymmetric setting employ obtain another exponent exponents: $r=7/5$
منابع مشابه
Turán Problems for Bipartite Graphs ∗
We consider an infinite version of the bipartite Turán problem. Let G be an infinite graph with V (G) = N, and let Gn be the n-vertex subgraph of G induced by the vertices {1, 2, . . . , n}. We show that if G is K2,t+1-free, then for infinitely many n, e(Gn) ≤ 0.471 √ tn3/2. Using the K2,t+1-free graphs constructed by Füredi, we construct an infinite K2,t+1-free graph with e(Gn) ≥ 0.23 √ tn3/2 ...
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Article history: Received 12 October 2012 Available online 14 February 2014
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ژورنال
عنوان ژورنال: Combinatorics, Probability & Computing
سال: 2021
ISSN: ['0963-5483', '1469-2163']
DOI: https://doi.org/10.1017/s0963548321000341