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 A026582 #7 Jun 23 2013 12:09:09
%S A026582 1,3,8,20,50,125,314,792,2003,5079,12897,32798,83478,212657,542040,
%T A026582 1382376,3526916,9001805,22982298,58691692,149919707,383028163,
%U A026582 978768731,2501494110,6394118165,16346237219,41793150985,106865638630
%N A026582 a(n) = Sum{T(i,j)}, 0<=j<=i, 0<=i<=n, T given by A026568.
%F A026582 Conjecture: n*a(n) +2*(-2*n+1)*a(n-1) +2*(-n+3)*a(n-2) +20*(n-2)*a(n-3) +(-7*n+6)*a(n-4) +2*(-12*n+41)*a(n-5) +8*(2*n-7)*a(n-6)=0. - _R. J. Mathar_, Jun 23 2013
%K A026582 nonn
%O A026582 0,2
%A A026582 _Clark Kimberling_