Erdős Problem #568

Let $G$ be a graph such that $R(G,T_n)\ll n$ for any tree $T_n$ on $n$ vertices and $R(G,K_n)\ll n^2$. Is it true that, for any $H$ with $m$ edges and no isolated vertices,\[R(G,H)\ll m?\]

#568: [EFRS93]

graph theory | ramsey theory

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In other words, is $G$ Ramsey size linear?

See also the entry in the graphs problem collection.

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