Number of 9's in n!. 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 2, 1, 0, 1, 0, 2, 1, 0, 0, 1, 3, 0, 1, 2, 2, 1, 1, 0, 4, 2, 1, 2, 2
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