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 A027233 #8 Oct 25 2019 10:00:38
%S A027233 1,7,34,184,785,4107,16894,88397,358212,1892182,7609892,40695540,
%T A027233 162938176,882569071,3523144085,19320028921,76956041950,426863069443,
%U A027233 1697410759579,9513773568608,37779519792187,213739273560729,847809431322520,4836704323382544,19167125562029304
%N A027233 a(n) = Sum_{k=0..n-2} T(n,k) * T(n,k+2), with T given by A026758.
%K A027233 nonn
%O A027233 2,2
%A A027233 _Clark Kimberling_
%E A027233 More terms from _Sean A. Irvine_, Oct 24 2019