[0,1,2,4,3,7,6,5,12,11,10,9,8,21,20,19,18,17,16, 15,14,13,38,37,36,35,34,33,32,31,30,29,28,27,26, 25,24,23,22,68,67,66,65,64,63,62,61,60,59,58,57, 56,55,54,53,52,51,50,49,48,47,46,45,44,43,42,41, 40,39]