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 A026870 #4 Mar 30 2012 18:56:11 %S A026870 1,14,125,911,5920,35785,205991,1145389,6208974,33019048,173020608, %T A026870 896198760,4599517316,23431544274,118650995097,597852859509, %U A026870 3000150410123,15004346987002,74827169741248,372278740384010,1848449139166668 %N A026870 T(2n,n-4), T given by A026758. %K A026870 nonn %O A026870 4,2 %A A026870 _Clark Kimberling_