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 A217203 #11 Oct 21 2013 11:10:08
%S A217203 0,1,2,7,28,131,690,4033,25864,180265,1354458,10898823,93407828,
%T A217203 848739867,8143768538,82229315137,871067808272,9654457636241,
%U A217203 111688595475634,1345725966256071,16854833617813388,219050429104638707,2949276326665620482,41076923039499915393
%N A217203 First column of A217202.
%F A217203 G.f.: T(0)/x - 1/x, where T(k) = 1 - x^2*(k+1)/( x^2*(k+1) - (1-2*x*k)*(1-2*x-2*x*k)/T(k+1) ); (continued fraction). - _Sergei N. Gladkovskii_, Oct 19 2013
%o A217203 (PARI) lista(m) = {P = x; M = subst(P, x, 1); print1(polcoeff(M, 0, q), ", "); Q = 2*x; M = subst(Q, x, 1); print1(polcoeff(M, 0, q), ", "); for (n=3, m, newP = n*q*Q+ 2*q*(1-q)*deriv(Q,q)+2*x*(1-q)*deriv(Q,x)+n*x*P; M = subst(newP, x, 1); print1(polcoeff(M, 0, q), ", "); P = Q; Q = newP;);} \\ _Michel Marcus_, Feb 12 2013
%Y A217203 Cf. A217202.
%K A217203 nonn
%O A217203 1,3
%A A217203 _N. J. A. Sloane_, Sep 27 2012
%E A217203 More terms from _Michel Marcus_, Feb 12 2013