[1,4,2,5,7,3,6,8,10,4,7,9,11,13,5,8,10,12,14,16,6, 9,11,13,15,17,19,7,10,12,14,16,18,20,22,8,11,13, 15,17,19,21,23,25,9,12,14,16,18,20,22,24,26,28,10]