

A224886


Number of unlabeled tournaments which do not contain a transitive ntournament.


0




OFFSET

0,3


COMMENTS

The empty tournament is considered.


LINKS

Table of n, a(n) for n=0..4.
John W. Moon, Topics on tournaments, Holt, Rinehard and Winston (1968).


EXAMPLE

For n=4, the a(4)= 13 solutions are the 5 tournaments on at most three vertices (the empty tournament is counted), 3 tournaments on four vertices, 3 tournaments on five vertices, 1 tournament on seven vertices (the Paley tournament on P_7 on seven vertices) and 1 tournament on six vertices (the tournament obtained from P_7 by deleting one vertex).
Notice that the tournaments on at most six vertices are listed in the Moon reference.


CROSSREFS

Sequence in context: A287059 A059085 A030064 * A180500 A176990 A109928
Adjacent sequences: A224883 A224884 A224885 * A224887 A224888 A224889


KEYWORD

nonn,more


AUTHOR

Houmem Belkhechine, Jul 24 2013


STATUS

approved



