[0,0,0,1,0,1,1,2,0,2,3,4,2,3,4,5,0,3,4,5,6,7,3,4, 5,6,7,8,9,10,0,4,6,7,8,9,10,11,12,13,4,5,7,8,9,10, 11,12,13,14,15,16,0,5,8,9,10,11,12,13,14,15,16,17, 18,19,20]