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 A351971 #9 May 30 2022 09:54:20
%S A351971 1,1,1,1,2,6,16,36,72,136,256,496,992,2016,4096,8256,16513,32913,
%T A351971 65689,131785,266482,544230,1124344,2352188,4984968,10699656,23244976,
%U A351971 51072256,113370112,253930816,573005056,1300390016,2962852353,6766967329,15472840497
%N A351971 a(0) = 1; a(n) = Sum_{k=0..floor(n/4)} binomial(n,4*k) * a(k).
%H A351971 Seiichi Manyama, <a href="/A351971/b351971.txt">Table of n, a(n) for n = 0..1000</a>
%F A351971 G.f. A(x) satisfies: A(x) = A(x^4/(1 - x)^4) / (1 - x).
%F A351971 E.g.f.: exp(x) * Sum_{n>=0} a(n) * x^(4*n) / (4*n)!.
%t A351971 a[0] = 1; a[n_] := a[n] = Sum[Binomial[n, 4 k] a[k], {k, 0, Floor[n/4]}]; Table[a[n], {n, 0, 34}]
%t A351971 nmax = 34; A[_] = 1; Do[A[x_] = A[x^4/(1 - x)^4]/(1 - x) + O[x]^(nmax + 1) // Normal, nmax + 1]; CoefficientList[A[x], x]
%Y A351971 Cf. A027826, A351970, A352066.
%K A351971 nonn
%O A351971 0,5
%A A351971 _Ilya Gutkovskiy_, Feb 26 2022