X ( 2 , 10 , 3 , 9 ) X ( 4 , 2 , 5 , 1 ) X ( 5 , 19 , 6 , 18 ) X ( 7 , 20 , 8 , 21 ) X ( 10 , 4 , 11 , 3 ) X ( 11 , 17 , 12 , 16 ) X ( 13 , 6 , 14 , 7 ) X ( 15 , 9 , 16 , 8 ) X ( 17 , 1 , 18 , 22 ) X ( 19 , 15 , 20 , 14 ) X ( 21 , 12 , 22 , 13 ) {\displaystyle X(2,10,3,9)X(4,2,5,1)X(5,19,6,18)X(7,20,8,21)X(10,4,11,3)X(11,17,12,16)X(13,6,14,7)X(15,9,16,8)X(17,1,18,22)X(19,15,20,14)X(21,12,22,13)}