Hilbert cubes in progression-free sets and in the set of squares II
  Let $S_2$ be the set of integer squares. We show that the dimension $d$ of a Hilbert cube $a_0+\{0,a_1\}+...+ \{0, a_d\}\subset S_2$ is bounded by $d=O(\log \log N)$ 
Rainer Dietmann, Christian Elsholtz
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