login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A224886 Number of unlabeled tournaments which do not contain a transitive n-tournament. 0
0, 1, 2, 4, 13 (list; graph; refs; listen; history; text; internal format)
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

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified June 22 20:06 EDT 2021. Contains 345388 sequences. (Running on oeis4.)