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Russian Mathematical Olympiad

Number theory Difficulty 5.1 AIME, harder Prove it Russia

Given integers $x, y \in [2, 100]$ , prove that there exists a positive integer $n$ such that the number $x^2 + y^2$ is composite.

(S. Berlov, A. Belov)

Solution

11.8. См. решение задачи 10.8.

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