• Corpus ID: 119326112

On the rational Tur\'an exponents conjecture

@article{Kang2018OnTR,
  title={On the rational Tur\'an exponents conjecture},
  author={Dong Yeap Kang and Jaehoon Kim and Hong Liu},
  journal={arXiv: Combinatorics},
  year={2018}
}
The extremal number $\mathrm{ex}(n,F)$ of a graph $F$ is the maximum number of edges in an $n$-vertex graph not containing $F$ as a subgraph. A real number $r \in [1,2]$ is realisable if there exists a graph $F$ with $\mathrm{ex}(n , F) = \Theta(n^r)$. Several decades ago, Erd\H{o}s and Simonovits conjectured that every rational number in $[1,2]$ is realisable. Despite decades of effort, the only known realisable numbers are $0,1, \frac{7}{5}, 2$, and the numbers of the form $1+\frac{1}{m}$, $2… 

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