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APMO 2025 Problem 2

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Let α\alpha and β\beta be positive real numbers. Emerald makes a trip in the coordinate plane, starting off from the origin (0,0)(0,0) . Each minute she moves one unit up or one unit to the right, restricting herself to the region ∣x−y∣<2025|x - y|< 2025 , in the coordinate plane. By the time she visits a point (x,y)(x,y) she writes down the integer ⌊xα+yβ⌋\lfloor x\alpha +y\beta \rfloor on it. It turns out that Emerald wrote each non- negative integer exactly once. Find all the possible pairs (α,β)(\alpha ,\beta) for which such a trip would be possible.

Dataset text NuminaMath olympiads. Quoted with source.

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\alpha + \beta = 2

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