Triangle read by rows: T(n,k) is the number of unlabeled digraphs on n nodes with k arcs up to reversing the arcs, k=0..n*(n-1).

A126066

Triangle read by rows: T(n,k) is the number of unlabeled digraphs on n nodes with k arcs up to reversing the arcs, k=0..n*(n-1).

Terms

    a(0) =1a(1) =1a(2) =1a(3) =1a(4) =1a(5) =1a(6) =1a(7) =3a(8) =3a(9) =3a(10) =1a(11) =1a(12) =1a(13) =1a(14) =4a(15) =9a(16) =18a(17) =24a(18) =30a(19) =24a(20) =18a(21) =9a(22) =4a(23) =1a(24) =1a(25) =1a(26) =1a(27) =4a(28) =11a(29) =38

External references