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Let n≥2n\ge2n≥2 be an integer and let x1<x2<⋯<xnx_1<x_2<\cdots<x_nx1<x2<⋯<xn be real numbers satisfying
Determine all possible values of nnn and all corresponding tuples (x1,x2,…,xn)(x_1,x_2,\ldots,x_n)(x1,x2,…,xn).