[1,2,3,2,4,3,4,2,5,4,5,4,5,3,5,4,5,2,6,5,6,5,6,5, 6,4,6,5,6,5,6,5,6,4,6,5,6,5,6,3,6,5,6,5,6,5,6,4,6, 5,6,2,7,6,7,6,7,6,7,6,7,5,7,6,7,6,7,6,7,6,7,5,7,6, 7,6,7,6,7,6,7]