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