For any sequence of real numbers A = {A_1, A_2, A_3, ... }, define *A to be the sequence {A_2 - A_1, A_3 - A_2, A_4 - A_3,..}. Suppose that all of the terms of the sequence *(*A) are 1, and that A_19 = A_92 = 0. Find A_1.

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