OPEN
This is open, and cannot be resolved with a finite computation.
Is there a graph of chromatic number $\aleph_1$ such that for all $\epsilon>0$ if $n$ is sufficiently large and $H$ is a subgraph on $n$ vertices then $H$ contains an independent set of size $>n^{1-\epsilon}$?
Conjectured by Erdős, Hajnal, and Szemerédi
[EHS82]. In
[Er95d] Erdős suggests this may even be true with an independent set of size $\gg n$.
See also
[750].
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T. F. Bloom, Erdős Problem #75, https://www.erdosproblems.com/75, accessed 2026-01-16