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 A371990 #7 Apr 15 2024 09:46:05
%S A371990 1,8,0,-256,2048,8192,-327680,2097152,27262976,-612368384,2013265920,
%T A371990 82409684992,-1249835483136,-996432412672,239418656948224,
%U A371990 -2495891395051520,-17018240974716928,669901648478339072,-4349632815109767168,-80937285128219000832
%N A371990 G.f. A(x) satisfies A(x) = ( 1 + 16*x*A(x)*(1 + A(x)) )^(1/4).
%F A371990 a(n) = 16^n * Sum_{k=0..n} binomial(n,k) * binomial(n/4+k/4+1/4,n)/(n+k+1).
%o A371990 (PARI) a(n) = 16^n*sum(k=0, n, binomial(n, k)*binomial(n/4+k/4+1/4, n)/(n+k+1));
%Y A371990 Cf. A000302, A371989.
%K A371990 sign
%O A371990 0,2
%A A371990 _Seiichi Manyama_, Apr 15 2024