A224886 Number of unlabeled tournaments which do not contain a transitive n-tournament.
0, 1, 2, 4, 13
Offset: 0
Examples
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.
Links
- John W. Moon, Topics on tournaments, Holt, Rinehard and Winston (1968).
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