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 A027295 #8 Oct 26 2019 23:16:46
%S A027295 1,4,15,52,195,676,2555,8976,34098,121448,463067,1669340,6384287,
%T A027295 23251620,89157557,327523680,1258803182,4658150520,17940605163,
%U A027295 66803546472,257777882894,965023761064,3730202020650,14029655954272,54315578806820,205120107930192
%N A027295 a(n) = Sum_{k=0..m-1} T(n,k) * T(n,k+1), where m=n for n=0,1 and m=floor((n+3)/2) for n >= 2, and T given by A026022.
%K A027295 nonn
%O A027295 1,2
%A A027295 _Clark Kimberling_
%E A027295 More terms from _Sean A. Irvine_, Oct 26 2019