av-j n1 1 j np1 1 n1 n1 12 n1 ng1 1 np1 crd 1 n1 av-j 1 n1 n2 1 crd j-jn 1 n1 j-jn 3 j-jn n1 4 n2 n1 2 ng1 j 1 j n1 4 n1 j 4 np1 n2 1