

A224886


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


1




OFFSET

0,3


COMMENTS

The empty tournament is considered.


LINKS



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



KEYWORD

nonn,more


AUTHOR



STATUS

approved



