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