Irregular triangle read by rows: T(n,k) = number of directed graphs-with-loops with n nodes and k arcs (n >= 0, 0 <= k <= n^2).

A046858

Irregular triangle read by rows: T(n,k) = number of directed graphs-with-loops with n nodes and k arcs (n >= 0, 0 <= k <= n^2).

Terms

    a(0) =1a(1) =1a(2) =1a(3) =1a(4) =2a(5) =4a(6) =2a(7) =1a(8) =1a(9) =2a(10) =8a(11) =17a(12) =24a(13) =24a(14) =17a(15) =8a(16) =2a(17) =1a(18) =1a(19) =2a(20) =9a(21) =32a(22) =95a(23) =203a(24) =373a(25) =515a(26) =584a(27) =515a(28) =373a(29) =203

External references