arXiv · 2609.23327
We present a construction with seven points on a circle that is not Ramsey, disproving a conjecture of Erdős, Graham, Montgomery, Rothschild, Spencer and Straus.
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Dömötör Pálvölgyi. 2026-09-20. A cyclic non-Ramsey heptagon. https://arxiv.org/abs/2609.23327
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