n1 n2 2 n1 j-jn 1 n1 n1 7 n2 j 3 np1 crd 1 j n2 5 j-jn j 1 j np1 1 crd j 1 j j 1 n2 n2 2 n2 n1 3 j n1 3 n2 ng1 1 ng1 j 1 np1 n1 1 n1 j 3