X ( 1 , 19 , 2 , 18 ) X ( 3 , 21 , 4 , 20 ) X ( 5 , 23 , 6 , 22 ) X ( 7 , 25 , 8 , 24 ) X ( 9 , 27 , 10 , 26 ) X ( 11 , 29 , 12 , 28 ) X ( 13 , 31 , 14 , 30 ) X ( 15 , 33 , 16 , 32 ) X ( 17 , 1 , 18 , 34 ) X ( 19 , 3 , 20 , 2 ) X ( 21 , 5 , 22 , 4 ) X ( 23 , 7 , 24 , 6 ) X ( 25 , 9 , 26 , 8 ) X ( 27 , 11 , 28 , 10 ) X ( 29 , 13 , 30 , 12 ) X ( 31 , 15 , 32 , 14 ) X ( 33 , 17 , 34 , 16 ) {\displaystyle X(1,19,2,18)X(3,21,4,20)X(5,23,6,22)X(7,25,8,24)X(9,27,10,26)X(11,29,12,28)X(13,31,14,30)X(15,33,16,32)X(17,1,18,34)X(19,3,20,2)X(21,5,22,4)X(23,7,24,6)X(25,9,26,8)X(27,11,28,10)X(29,13,30,12)X(31,15,32,14)X(33,17,34,16)}