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 A099529 #8 Jun 13 2015 00:51:34
%S A099529 1,0,0,-1,2,-3,5,-9,16,-28,49,-86,151,-265,465,-816,1432,-2513,4410,
%T A099529 -7739,13581,-23833,41824,-73396,128801,-226030,396655,-696081,
%U A099529 1221537,-2143648,3761840,-6601569,11584946,-20330163,35676949,-62608681,109870576,-192809420,338356945,-593775046,1042002567
%N A099529 Expansion of (1+x)^2/((1+x)^2+x^3).
%C A099529 Binomial transform has g.f. 1/(1-x+x^3) (A050935(n+2)).
%H A099529 <a href="/index/Rec#order_03">Index entries for linear recurrences with constant coefficients</a>, signature (-2,-1,-1).
%F A099529 a(n)=-2a(n-1)-a(n-2)-a(n-3); a(n)=sum{j=0..n, sum{k=0..floor(j/3), C(n, j)(-1)^(n-j)C(j-2k, k)(-1)^k}}.
%F A099529 a(n)=(-1)^n*A005314(n-2). [From _R. J. Mathar_, Nov 26 2008]
%K A099529 easy,sign
%O A099529 0,5
%A A099529 _Paul Barry_, Oct 20 2004