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 A048209 #5 Mar 30 2012 18:56:54
%S A048209 1,5,17,37,77,137,235,355,499,709,951,1251,1589,1981,2476,3020,3615,
%T A048209 4263,4985,5785,6667,7679,8783,9959,11209,12587,14126,15806,17604,
%U A048209 19524,21539,23779,26320,29040,31875,34863,38008,41276
%N A048209 a(n)=Sum{T(n,j): j=1,2,...,n}, array T given by A048201.
%K A048209 nonn
%O A048209 1,2
%A A048209 _Clark Kimberling_