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