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 A127089 #8 Jan 30 2020 22:03:32
%S A127089 1,1,5,32,239,1981,17757,169765,1717730,18311250,205075693,2408303246,
%T A127089 29611689597,380712483013,5111573917042,71576222215342,
%U A127089 1043901890068909,15835797676490439,249530033466698385,4078781718332965858
%N A127089 Convolution 4th root of column 3 (A127086) of triangle A127082.
%H A127089 G. C. Greubel, <a href="/A127089/b127089.txt">Table of n, a(n) for n = 0..80</a>
%t A127089 T[n_, k_]:= T[n, k]= If[k==n, 1, Coefficient[(1 + x*Sum[x^(r-k)*Sum[T[r, c], {c, k, r}], {r, k, n-1}] + x^(n+1))^(k+1), x, n-k]]; CoefficientList[Series[ (Sum[T[n, 3]*x^n, {n,0,25}]/x^3)^(1/4), {x,0,20}], x] (* _G. C. Greubel_, Jan 30 2020 *)
%Y A127089 Cf. A127082, A127083, A127084, A127085, A127086, A127087, A127088, A127090, A127091.
%K A127089 nonn
%O A127089 0,3
%A A127089 _Paul D. Hanna_, Jan 04 2007