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 A026651 #4 Mar 30 2012 18:56:09 %S A026651 1,9,40,240,915,5103,18704,101952,368490,1990890,7154928,38514528, %T A026651 138086403,742202055,2658662560,14283407616,51156225342,274842096462, %U A026651 984532674800,5291030979360,18960255044654,101937273452454,365451691152864 %N A026651 a(n) = T(2n,n-2), T given by A026648. %K A026651 nonn %O A026651 2,2 %A A026651 _Clark Kimberling_