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