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