A139628 -id:A139628 - cp's OEIS frontend

Showing 1-4 of 4 results.

A139623 Table read by rows: T(n,k) is the number of directed multigraphs with loops and no vertex of degree 0, with n arcs and k vertices, which are transitive (the existence of a path between two points implies the existence of an arc between those two points).

Original entry on oeis.org

1, 1, 1, 4, 3, 1, 1, 7, 12, 9, 3, 1, 1, 13

Offset: 1

Benoit Jubin, May 01 2008

Length of the n^th row: 2n.
T(n,1) = T(n,2n) = 1 and T(n,2n-1) = 3 if n>1.
Row sums: A139628.

			Triangle begins
1, 1;
1, 4, 3, 1;
1, 7, 12, 9, 3, 1;

Cf. A136564, A139624, A139625.

A139629 Row sums of A139624, number of connected directed multigraphs with loops and no vertex of degree 0, with n arcs, which are transitive (the existence of a path between two points implies the existence of an arc between those two points).

Original entry on oeis.org

1, 2, 6, 17

Offset: 0

Benoit Jubin, May 01 2008

Cf. A139628, A139630.

A139630 Row sums of A139625, number of strongly connected directed multigraphs with loops and no vertex of degree 0, with n arcs, which are transitive (the existence of a path between two points implies the existence of an arc between those two points).

Original entry on oeis.org

1, 1, 1, 1, 2, 3, 7, 11, 20, 30, 47, 71, 117, 201, 369, 703, 1323, 2463, 4446

Offset: 0

Benoit Jubin, May 01 2008

nonn

Cf. A139628, A139629.

A138352 Table read by antidiagonals: T(n,k) is the number of transitive directed multigraphs with loops with n arcs and k vertices.

Original entry on oeis.org

1, 1, 0, 1, 1, 0, 1, 2, 1, 0, 1, 2, 5, 1, 0, 1, 2, 8, 8, 1, 0, 1, 2, 9, 20, 14, 1, 0, 1, 2, 9, 29

Offset: 0

Benoit Jubin, May 07 2008

Partial sums of the rows of A139623, i.e., T(n,k) = sum(T139623(n,p),p=0..k).

If k>=2n, T(n,k) = A139628(n).

Showing 1-4 of 4 results.