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