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 A364337 #18 Mar 24 2025 22:33:40
%S A364337 1,2,9,68,580,5406,53270,545844,5757332,62094217,681653493,7591431752,
%T A364337 85558696024,974024788280,11184192097016,129378232148016,
%U A364337 1506363564912368,17639001584452320,207593804132718948,2454236122156830254,29132714097692056954,347086786035103983446
%N A364337 G.f. satisfies A(x) = (1 + x) * (1 + x*A(x)^4).
%H A364337 Seiichi Manyama, <a href="/A364337/b364337.txt">Table of n, a(n) for n = 0..907</a>
%F A364337 a(n) = Sum_{k=0..n} binomial(4*k+1,k) * binomial(4*k+1,n-k) / (4*k+1).
%t A364337 terms = 22; A[_] = 0; Do[A[x_] = (1+x)(1+x*A[x]^4) + O[x]^terms // Normal, terms]; CoefficientList[A[x], x] (* _Stefano Spezia_, Mar 24 2025 *)
%o A364337 (PARI) a(n) = sum(k=0, n, binomial(4*k+1, k)*binomial(4*k+1, n-k)/(4*k+1));
%Y A364337 Cf. A073157, A364336, A364338, A364339.
%Y A364337 Cf. A215623, A215715, A234461, A239107.
%K A364337 nonn
%O A364337 0,2
%A A364337 _Seiichi Manyama_, Jul 19 2023