X ( 1 , 15 , 2 , 14 ) X ( 3 , 17 , 4 , 16 ) X ( 5 , 19 , 6 , 18 ) X ( 7 , 21 , 8 , 20 ) X ( 9 , 23 , 10 , 22 ) X ( 11 , 25 , 12 , 24 ) X ( 13 , 1 , 14 , 26 ) X ( 15 , 3 , 16 , 2 ) X ( 17 , 5 , 18 , 4 ) X ( 19 , 7 , 20 , 6 ) X ( 21 , 9 , 22 , 8 ) X ( 23 , 11 , 24 , 10 ) X ( 25 , 13 , 26 , 12 ) {\displaystyle X(1,15,2,14)X(3,17,4,16)X(5,19,6,18)X(7,21,8,20)X(9,23,10,22)X(11,25,12,24)X(13,1,14,26)X(15,3,16,2)X(17,5,18,4)X(19,7,20,6)X(21,9,22,8)X(23,11,24,10)X(25,13,26,12)}
