

A051337


Number of strongly connected tournaments on n nodes.


2



1, 0, 1, 1, 6, 35, 353, 6008, 178133, 9355949, 884464590, 152310149735, 48234782263293, 28304491788158056, 30964247546702883729, 63468402142317299907481, 244785748571033855024746438
(list;
graph;
refs;
listen;
history;
text;
internal format)



OFFSET

1,5


COMMENTS

A tournament is strongly connected (or strong) if there is a directed path between any pair of points.


REFERENCES

F. Harary and E. M. Palmer, Graphical Enumeration, Academic Press, NY, 1973, p. 127, Eq. (5.2.4);
J. W. Moon, Topics on Tournaments, Holt, NY, 1968.
J. L. Gross and J. Yellen, eds., Handbook of Graph Theory, CRC Press, 2004; p. 523.


LINKS

Table of n, a(n) for n=1..17.


FORMULA

G.f.: = B(x)/(1+B(x)) where B(x) = g.f. for A000568.


CROSSREFS

Cf. A000568, A054946.
Sequence in context: A167579 A030446 A093989 * A192996 A192997 A152128
Adjacent sequences: A051334 A051335 A051336 * A051338 A051339 A051340


KEYWORD

nonn,nice,easy


AUTHOR

Vladeta Jovovic


STATUS

approved



