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