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 A110126 #3 Mar 30 2012 18:59:08
%S A110126 1,0,-1,2,11,12,19,174,1073,6584,45871,337098,2563293,20346204,
%T A110126 169904575,1501012310,14065496355,139601710224,1460544299739,
%U A110126 16007830782402,182743810845223,2163753452707580,26506423427738891,335585442530912862,4389743577358599363
%N A110126 Diagonal sums of a scaled Legendre triangle.
%C A110126 Diagonal sums of A110124.
%F A110126 a(n)=sum{k=0..floor(n/2), 2^(n-2k)*LegendreP(n-2k, k)}.
%K A110126 easy,sign
%O A110126 0,4
%A A110126 _Paul Barry_, Jul 13 2005