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 A027232 #8 Oct 25 2019 09:59:29
%S A027232 1,4,19,72,355,1347,6843,26077,135752,519336,2760110,10591394,
%T A027232 57299551,220393887,1210772453,4665698732,25974365600,100243916036,
%U A027232 564517479641,2181476412875,12407767954139,48002072364351,275392803316254,1066512702720864,6164746100658825,23896975393255717
%N A027232 a(n) = Sum_{k=0..n-1} T(n,k) * T(n,k+1), with T given by A026758.
%K A027232 nonn
%O A027232 1,2
%A A027232 _Clark Kimberling_
%E A027232 More terms from _Sean A. Irvine_, Oct 24 2019