%I #11 Aug 24 2023 07:50:01
%S 1,2,11,74,563,4604,39524,351322,3205699,29854250,282615379,
%T 2711494224,26307568324,257673017952,2544420045432,25303000558890,
%U 253184833958403,2547251287244918,25752086767703969,261480234091024906,2665405840919762043
%N G.f. satisfies A(x) = ( 1 + x*A(x)^2*(1 + x*A(x)) )^2.
%F If g.f. satisfies A(x) = ( 1 + x*A(x)^2*(1 + x*A(x))^s )^t, then a(n) = Sum_{k=0..n} binomial(t*(n+k+1),k) * binomial(s*k,n-k)/(n+k+1).
%o (PARI) a(n, s=1, t=2) = sum(k=0, n, binomial(t*(n+k+1), k)*binomial(s*k, n-k)/(n+k+1));
%Y Cf. A001002, A365154.
%K nonn
%O 0,2
%A _Seiichi Manyama_, Aug 23 2023
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