

A139624


Table 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, which are transitive (the existence of a path between two points implies the existence of an arc between those two points).


4



1, 1, 1, 3, 2, 1, 6, 7, 3, 1, 11
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OFFSET

1,4


COMMENTS

Length of the n^th row: n+1.
T(n,1) = 1
Row sums: A139629.


LINKS

Table of n, a(n) for n=1..11.


EXAMPLE

Triangle begins
1;
1, 1;
3, 2, 1;
6, 7, 3, 1;


CROSSREFS

Cf. A139623, A139625.
Sequence in context: A060408 A267121 A208518 * A132276 A257558 A202390
Adjacent sequences: A139621 A139622 A139623 * A139625 A139626 A139627


KEYWORD

nonn,tabl


AUTHOR

Benoit Jubin, May 01 2008


STATUS

approved



