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