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