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 A370473 #15 Apr 04 2024 09:47:11
%S A370473 1,1,4,25,185,1501,12914,115723,1068505,10094770,97117624,948181724,
%T A370473 9370734322,93562986440,942385174150,9563720899515,97696642766654,
%U A370473 1003789888620166,10366477185870960,107548800153957745,1120374840689934195,11714707429579539268
%N A370473 G.f. satisfies A(x) = 1 + x * A(x)^2 * (1 - A(x) + A(x)^2 - A(x)^3 + A(x)^4).
%F A370473 G.f. A(x) satisfies:
%F A370473 (1) A(x)^2 = 1 + x * A(x)^2 * (1 + A(x)^5).
%F A370473 (2) A(x) = sqrt(B(x)) where B(x) is the g.f. of A366401.
%F A370473 a(n) = Sum_{k=0..n} binomial(n,k) * binomial(n+5*k/2+1/2,n)/(2*n+5*k+1).
%o A370473 (PARI) a(n) = sum(k=0, n, binomial(n, k)*binomial(n+5*k/2+1/2, n)/(2*n+5*k+1));
%Y A370473 Cf. A000108, A219537.
%Y A370473 Cf. A370472, A370476.
%Y A370473 Cf. A366401.
%K A370473 nonn
%O A370473 0,3
%A A370473 _Seiichi Manyama_, Mar 31 2024