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%I #7 Apr 12 2024 10:48:17
%S 1,1,2,0,-6,12,67,-152,-740,2296,9017,-35979,-113936,579516,1454975,
%T -9493390,-18317155,157178640,220172289,-2618995381,-2377680689,
%U 43783556265,19149194005,-732638868460,16196837316,12246524817736,-5891297294673
%N G.f. A(x) satisfies A(x) = 1 - x/A(x)^4 * (1 - A(x) - A(x)^5).
%F a(n) = (1/n) * Sum_{k=0..n} binomial(n,k) * binomial(n-5*k,n-k-1) for n > 0.
%o (PARI) a(n) = if(n==0, 1, sum(k=0, n, binomial(n, k)*binomial(n-5*k, n-k-1))/n);
%Y Cf. A349332, A367725, A371914, A371915.
%Y Cf. A371889, A371890.
%K sign
%O 0,3
%A _Seiichi Manyama_, Apr 12 2024