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 A026897 #4 Mar 30 2012 18:56:11 %S A026897 1,11,80,489,2732,14512,74888,380329,1916709,9637687,48528434, %T A026897 245289395,1246499970,6374296278,32816505566,170106486358, %U A026897 887697088316,4662338571684,24636365887246,130918389450108,699335986465354 %N A026897 T(2n,n+4), T given by A026780. %K A026897 nonn %O A026897 4,2 %A A026897 _Clark Kimberling_