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 A026889 #4 Mar 30 2012 18:56:11 %S A026889 1,7,37,178,825,3774,17250,79326,368516,1733597,8268603,40003178, %T A026889 196273837,976066486,4915503146,25042730042,128927697340,670023585820, %U A026889 3511276691660,18537816521102,98514404946264,526575421631986 %N A026889 T(2n+1,n+3), T given by A026769. %K A026889 nonn %O A026889 2,2 %A A026889 _Clark Kimberling_