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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

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Last modified September 1 03:55 EDT 2014. Contains 246282 sequences.