[0,1,1,2,2,3,2,4,4,5,4,6,5,6,5,7,6,8,6,8,8,8,6,9, 9,9,10,11,10,11,9,12,12,12,11,14,13,13,11,14,12, 14,12,13,14,15,12,15,15,15,14,16,14,17,15,17,17, 16,14,17,15,16,14,19,18,20,18,18,18,20,17,20,19, 19,19,20,19,21]