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 A372107 #6 Apr 19 2024 10:30:57
%S A372107 1,2,8,38,198,1094,6296,37338,226596,1400518,8785524,55793170,
%T A372107 358000418,2317478554,15116570956,99259594982,655580568854,
%U A372107 4352370307750,29028865425828,194416887461778,1306961109488350,8815875534728018,59650171332148564
%N A372107 G.f. A(x) satisfies A(x) = 1/( 1 - 4*x/(1 - x*A(x)) )^(1/2).
%F A372107 a(n) = Sum_{k=0..n} 4^k * binomial(n/2+k/2-1/2,k) * binomial(n-1,n-k)/(n-k+1).
%o A372107 (PARI) a(n) = sum(k=0, n, 4^k*binomial(n/2+k/2-1/2, k)*binomial(n-1, n-k)/(n-k+1));
%Y A372107 Cf. A372088.
%K A372107 nonn
%O A372107 0,2
%A A372107 _Seiichi Manyama_, Apr 19 2024