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Erdős problem 56

Suppose A⊆{1,…,N}A \subseteq \{1,\dots,N\} is such that there are no k+1k+1 elements of AA which are relatively prime. An example is the set of all multiples of the first kk primes. Is this the largest such set? To avoid trivial counterexamples, we must insist that NN be at least the kkth prime.

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  • Formalization

    Erdős AI contributions wiki · 25 Nov, 2025-27 May, 2026

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