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 A026678 #4 Mar 30 2012 18:56:10 %S A026678 1,1,4,5,17,23,73,103,314,455,1350,1993,5798,8679,24872,37633,106573, %T A026678 162643,456169,701075,1950697,3015563,8334539,12948083,35582783, %U A026678 55513327,151809737,237705547,647279131,1016736115,2758310121 %N A026678 a(n) = T(n,0) + T(n,1) + ... + T(n,[ n/2 ]), T given by A026670. %K A026678 nonn %O A026678 0,3 %A A026678 _Clark Kimberling_