1, 10, 11, 12, 13, 14, 15, 17, 19, 2, 21, 3, 4, 6, 7, 8
1, 10, 11, 12, 13, 14, 15, 17, 19, 2, 21, 3, 4, 6, 7, 8, 11, 12, 13, 15, 2, 5, 6, 7