Erdős Problem #42

Let $M\geq 1$ and $N$ be sufficiently large in terms of $M$. Is it true that for every Sidon set $A\subset \{1,\ldots,N\}$ there is another Sidon set $B\subset \{1,\ldots,N\}$ of size $M$ such that $(A-A)\cap(B-B)=\{0\}$?

#42: [Er95]

number theory | sidon sets | additive combinatorics

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This page was last edited 14 September 2025.

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Currently working on this problem	Gusarich
This problem looks difficult	None
This problem looks tractable	BorisAlexeev

Additional thanks to: Zach Hunter

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