A117970 Position of first 0 counting from the least significant digit in the ternary expansion of 2^n.

0, 0, 0, 0, 3, 2, 2, 4, 4, 5, 4, 2, 2, 4, 0, 3, 4, 2, 2, 3, 3, 8, 3, 2, 2, 5, 5, 6, 5, 2, 2, 11, 4, 3, 5, 2, 2, 3, 3, 11, 3, 2, 2, 5, 8, 4, 5, 2, 2, 13, 5, 3, 5, 2, 2, 3, 3, 4, 3, 2, 2, 4, 4, 7, 4, 2, 2, 4, 6, 3, 4, 2, 2, 3, 3, 7, 3, 2, 2, 6, 6, 7, 6, 2, 2, 10, 4, 3, 7, 2, 2, 3, 3, 5, 3, 2, 2, 11, 5, 4, 17