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 A129883 #5 Mar 30 2013 04:51:25
%S A129883 2,0,2,2,10,6,34,88
%N A129883 Sequence i_{h_n} arising in enumeration of arrays of directed blocks (see Quaintance reference for precise definition), where i_n = A129876, h_n = A129874.
%D A129883 Jocelyn Quaintance, Combinatoric Enumeration of Two-Dimensional Proper Arrays, Discrete Math., 307 (2007), 1844-1864.
%F A129883 See Quaintance reference for generating functions that produce A129872-A129886.
%K A129883 nonn,more
%O A129883 1,1
%A A129883 _N. J. A. Sloane_, May 26 2007