This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A224886 #18 Sep 13 2013 21:30:06 %S A224886 0,1,2,4,13 %N A224886 Number of unlabeled tournaments which do not contain a transitive n-tournament. %C A224886 The empty tournament is considered. %H A224886 John W. Moon, <a href="http://www.gutenberg.org/ebooks/42833">Topics on tournaments</a>, Holt, Rinehard and Winston (1968). %e A224886 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). %e A224886 Notice that the tournaments on at most six vertices are listed in the Moon reference. %K A224886 nonn,more %O A224886 0,3 %A A224886 _Houmem Belkhechine_, Jul 24 2013