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Problem 2184

IMO Shortlist mid-range; USAMO P2/P5
Number theory Difficulty 8.0 Prove it KöMaL problem A · Hungary · 2022

Let qq be a monic polynomial with integer coefficients. Prove that there exists a constant CC depending only on polynomial qq such that for an arbitrary prime number pp and an arbitrary positive integer NpN\le p the congruence n!q(n)(modp)n! \equiv q(n) \pmod{p} has at most CN2/3CN^{2/3} solutions among any NN consecutive integers.

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