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Erdős problem 689

Let n be sufficiently large. Is there some choice of congruence class a_p for all primes 2 ≤ p ≤ n such that every integer in [1,n] satisfies at least two of the congruences ≡ a_p (mod p)?

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  • AI collaborating with humans

    Erdős AI contributions wiki · 29 Oct, 2025-2 Jun, 2026

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    Boris Alexeev, Przemek Chojecki, Dogmachine, jleng01, Mehtaab Sawhney, Terence Tao, Malek Zribi
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