[2,3,2,3,4,2,3,5,3,5,2,6,3,4,7,2,3,7,5,8,2,3,5,9, 3,4,9,2,6,10,3,11,2,3,5,7,11,4,5,7,12,2,3,13,3,8, 13,2,6,14,3,4,5,9,15,2,3,5,9,15,7,16,2,3,7,10,17, 3,4,17,2,5,6,11,18,3,5,8,11,19,2,3,19,4,12,20,2,3, 7]