Triangle read by rows: T(n,k) is the number of connected directed multigraphs with loops and no vertex of degree 0, with n arcs and k vertices.

A139621

Triangle read by rows: T(n,k) is the number of connected directed multigraphs with loops and no vertex of degree 0, with n arcs and k vertices.

Terms

    a(0) =1a(1) =1a(2) =1a(3) =1a(4) =4a(5) =3a(6) =1a(7) =8a(8) =15a(9) =8a(10) =1a(11) =16a(12) =57a(13) =66a(14) =27a(15) =1a(16) =25a(17) =163a(18) =353a(19) =295a(20) =91a(21) =1a(22) =40a(23) =419a(24) =1504a(25) =2203a(26) =1407a(27) =350a(28) =1a(29) =56

External references