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 A156129 #6 Sep 28 2013 02:37:11 %S A156129 1,2,9,58,501,5402,69909,1055458,18211401,353506802,7624471809, %T A156129 180889942858,4681743794301,131269240120202,3963720131525709, %U A156129 128234893954822258,4425253713052509201,162255367355408805602,6299173242134303391609,258136328705500135053658 %N A156129 Q_n(2) (see A104035). %F A156129 G.f.: 1/Q(0), where Q(k) = 1 - 2*x*(2*k+1) - 5*x^2*(k+1)^2/Q(k+1); (continued fraction). - _Sergei N. Gladkovskii_, Sep 28 2013 %K A156129 nonn %O A156129 0,2 %A A156129 _N. J. A. Sloane_, Nov 06 2009