Erdős problem 888 · problems.science

What is the size of the largest $A\subseteq \{1,\ldots,n\}$ such that if $a\leq b\leq c\leq d\in A$ are such that $abcd$ is a square then $ad=bc$ ?

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AI standalone
Erdős AI contributions wiki · 18 Jan, 2026
Machine
Claude Opus 4.5, Gemini 3 Pro, GPT-5.2 Thinking
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AI collaborating with humans
Erdős AI contributions wiki · 25 Apr, 2026
Machine
Aristotle, GPT-5.5 Pro
People
Przemek Chojecki
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Subtle errors
GPT-Erdős
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argument
VibeMathed
Machine
Aristotle, GPT-5.5 Pro
People
Przemek Chojecki
Reported outcome
resolved
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