A037889 (1/2)*Sum{|d(i)-e(i)|} where Sum{d(i)*3^i} is base 3 representation of n and e(i) are digits d(i) in reverse order.

0, 0, 1, 0, 1, 2, 1, 0, 1, 0, 1, 1, 0, 1, 1, 0, 1, 2, 1, 0, 2, 1, 0, 2, 1, 0, 1, 0, 1, 2, 1, 2, 3, 2, 3, 2, 1, 2, 1, 0, 1, 2, 1, 2, 3, 2, 3, 2, 1, 2, 1, 0, 1, 2, 1, 0, 3, 2, 1, 4, 3, 2, 3, 2, 1, 2, 1, 0, 3, 2, 1, 4, 3, 2, 3, 2, 1, 2, 1, 0, 1, 0, 1, 2, 1, 2, 3, 2, 3, 1