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A121272 Number of outcomes of unlabeled n-team round-robin tournaments that are not uniquely defined by their score vectors. 0
0, 0, 0, 0, 5, 45, 438, 6849, 191483, 9732967, 903753099, 154108310917, 48542114686488, 28401423719121589, 31021002160355165644, 63530415842308265098260, 244912778438520759443242406 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,5

COMMENTS

This sequence is the difference between A000568 (Number of outcomes of unlabeled n-team round-robin tournaments) and A000570 (Number of tournaments on n nodes determined by their score vectors).

LINKS

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

Score Sequence at MathWorld.

EXAMPLE

All tournaments with 4 or less teams are uniquely defined by their score vectors. Hence a(1) = a(2) = a(3) = a(4) = 0.

For five team tournaments only two score sequences are do not define the tournament uniquely: {1,1,2,3,3} and {1,2,2,2,3}. The first sequence corresponds to two different tournaments and the second sequence to three different tournaments. Thus a(5) = 5.

CROSSREFS

Sequence in context: A058410 A005979 A165225 * A054318 A093140 A137233

Adjacent sequences:  A121269 A121270 A121271 * A121273 A121274 A121275

KEYWORD

nonn

AUTHOR

Tanya Khovanova, Aug 23 2006

STATUS

approved

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Last modified May 23 02:46 EDT 2017. Contains 286909 sequences.