Let a0=0<a1<a2<…<an be integers such that the sequence bk=2k+1ak+1−ak (k=0, 1, …, n−1) is non-decreasing. Suppose that c1, c2, …, cn are real numbers such that the polynomial 1+∑k=1nckxak is divisible by the polynomial (x+1)n. Show that 2>∣c1∣>∣c2∣>…>∣cn∣.
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