A025687 Exponent of 10 (value of j) in n-th number of form 5^i*10^j.

0, 0, 1, 0, 1, 2, 0, 1, 2, 0, 3, 1, 2, 0, 3, 1, 4, 2, 0, 3, 1, 4, 2, 0, 5, 3, 1, 4, 2, 0, 5, 3, 1, 6, 4, 2, 0, 5, 3, 1, 6, 4, 2, 0, 7, 5, 3, 1, 6, 4, 2, 0, 7, 5, 3, 1, 8, 6, 4, 2, 0, 7, 5, 3, 1, 8, 6, 4, 2, 9, 0, 7, 5, 3, 1, 8, 6, 4, 2, 9, 0, 7, 5, 3, 10, 1, 8, 6, 4, 2, 9, 0, 7, 5, 3, 10, 1, 8, 6, 4, 11, 2, 9, 0, 7, 5