[1,2,1,3,1,3,2,4,1,4,3,5,1,5,2,5,3,5,4,6,1,6,5,7,1,7,2,7,3,7,4,7,5,7,6,8,1,8,3,8,5,8,7,9,1,9,2,9,4,9,5,9,7,9,8,10,1,10,3,10,7,10,9,11,1,11,2,11,3,11,4,11,5,11,6,11,7,11,8,11,9,11,10,12,1,12,5,12,7,12,11,13,1,13]