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