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A136868
Table read by antidiagonals: T(n,k) is the number of connected directed multigraphs with loops 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).
1
1, 1, 0, 1, 1, 0, 1, 2, 1, 0, 1, 2, 4, 1, 0, 1, 2, 6, 7, 1, 0, 1, 2, 6, 14, 12, 1, 0, 1, 2, 6, 17
OFFSET
0,8
COMMENTS
Partial sums of the rows of A139624, i.e., T(n,k) = sum(T139624(n,p),p=0..k).
T(0,k) = 1 for k>=0; T(n,0) = 0 and T(n,1) = 1 for n>0.
If k>=n+1, T(n,k) = A139629(n).
EXAMPLE
Triangle begins:
1,
1, 0,
1, 1, 0,
1, 2, 1, 0,
1, 2, 4, 1, 0,
1, 2, 6, 7, 1, 0,
1, 2, 6,14,12, 1, 0,
CROSSREFS
Cf. A138352.
Sequence in context: A023444 A248157 A290428 * A276066 A145895 A114503
KEYWORD
more,nonn,tabl
AUTHOR
Benoit Jubin, May 11 2008
STATUS
approved