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