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 A027225 #9 Oct 25 2019 04:57:56
%S A027225 1,8,52,247,1416,6056,33731,139016,770116,3121259,17335095,69642995,
%T A027225 388958218,1554558921,8740670953,34818606079,197136480944,
%U A027225 783522002716,4466326137854,17722654061673,101674164224552,402960855102206,2325563749837462,9208279020729297,53433859702165884
%N A027225 a(n) = Sum_{k=0..n-2} T(n,k) * T(n,k+2), with T given by A026747.
%K A027225 nonn
%O A027225 2,2
%A A027225 _Clark Kimberling_
%E A027225 More terms from _Sean A. Irvine_, Oct 24 2019