Erdős problem 1125 · problems.science

Let $f:\mathbb{R}\to \mathbb{R}$ be such that $2f(x) \leq f(x+h)+f(x+2h)$ for every $x\in \mathbb{R}$ and $h>0$ . Must $f$ be monotonic?

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Erdős AI contributions wiki · 11 Apr, 2026
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Aristotle
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