Triangle read by rows: T(n,k) = number of labeled loopless digraphs with n nodes and k arcs (n >= 1, 0 <= k <= n*(n-1)).
A123554
Triangle read by rows: T(n,k) = number of labeled loopless digraphs with n nodes and k arcs (n >= 1, 0 <= k <= n*(n-1)).
Terms
- a(0) =1a(1) =1a(2) =2a(3) =1a(4) =1a(5) =6a(6) =15a(7) =20a(8) =15a(9) =6a(10) =1a(11) =1a(12) =12a(13) =66a(14) =220a(15) =495a(16) =792a(17) =924a(18) =792a(19) =495a(20) =220a(21) =66a(22) =12a(23) =1a(24) =1a(25) =20a(26) =190a(27) =1140a(28) =4845a(29) =15504
External references
- oeis: A123554