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 A054148 #4 Mar 30 2012 18:57:03 %S A054148 1,5,28,132,574,2380,9560,37536,144872,551696,2078464,7761600, %T A054148 28771168,105985984,388336256,1416262656,5144067200,18616720640, %U A054148 67159278592,241579840512,866744413696,3102440074240,11081272653824 %N A054148 T(2n+1,n), array T as in A054144. %K A054148 nonn %O A054148 0,2 %A A054148 _Clark Kimberling_, Mar 18 2000