Data:L11n359/PD Presentation

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