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