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