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 A379039 #9 Dec 14 2024 09:14:20
%S A379039 1,4,22,172,1513,14356,143228,1480956,15728516,170558634,1880568650,
%T A379039 21019304814,237615558790,2712066792304,31210387143556,
%U A379039 361738488066632,4218907281330372,49476183230651216,583066018329260673,6901459436855306662,82011678696864842013
%N A379039 G.f. A(x) satisfies A(x) = ( (1 + x) * (1 + x*A(x)^2) )^2.
%F A379039 G.f.: A(x) = B(x)^2 where B(x) is the g.f. of A364337.
%F A379039 a(n) = Sum_{k=0..n} binomial(4*k+2,k) * binomial(4*k+2,n-k)/(2*k+1).
%o A379039 (PARI) a(n) = sum(k=0, n, binomial(4*k+2, k)*binomial(4*k+2, n-k)/(2*k+1));
%Y A379039 Cf. A004798, A073155, A379037.
%Y A379039 Cf. A364337, A379038.
%K A379039 nonn
%O A379039 0,2
%A A379039 _Seiichi Manyama_, Dec 14 2024