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 A027296 #10 Aug 19 2022 12:47:27
%S A027296 1,6,22,100,345,1470,5096,21120,74175,302698,1076922,4352140,15660827,
%T A027296 62876490,228468272,913093664,3345466023,13326904266,49176362780,
%U A027296 195434713432,725586231766,2878605745972,10744342665072,42571577779200,159638882959595,631933882236306
%N A027296 a(n) = Sum_{k=0..floor((n-1)/2)} T(n,k) * T(n,k+2), with T given by A026022.
%Y A027296 Cf. A026022.
%K A027296 nonn
%O A027296 2,2
%A A027296 _Clark Kimberling_
%E A027296 More terms from _Sean A. Irvine_, Oct 26 2019