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