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 A027316 #12 Oct 27 2019 19:56:44
%S A027316 1,4,15,70,644,5502,46936,402164,3460536,29885592,258897792,
%T A027316 2248831350,19579288052,170814593158,1492927792104,13069310259850,
%U A027316 114576104658836,1005775588360122,8839355153926048,77768991557179442,684886480844420844,6037008171432448154
%N A027316 a(n) = Sum_{k=0..m-1} T(n,k) * T(n,k+1), where m=n for n=0,1,2,3; m=2n for n >= 4; and T is given by A026082.
%K A027316 nonn
%O A027316 1,2
%A A027316 _Clark Kimberling_
%E A027316 More terms from _Sean A. Irvine_, Oct 27 2019