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 A139629 #2 Mar 31 2012 10:31:22 %S A139629 1,2,6,17 %N A139629 Row sums of A139624, number of connected directed multigraphs with loops and no vertex of degree 0, with n arcs, which are transitive (the existence of a path between two points implies the existence of an arc between those two points). %Y A139629 Cf. A139628, A139630. %K A139629 more,nonn %O A139629 0,2 %A A139629 _Benoit Jubin_, May 01 2008