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