%I #9 Dec 25 2023 10:02:15
%S 1,7,97,2023,56257,1955527,81570337,3969606823,220777431937,
%T 13813838801287,960354511044577,73441487204670823,6126887497334519617,
%U 553733062241471461447,53894653951229272883617,5620230710788836168938023,625160202763025501303191297
%N Expansion of e.g.f. exp(x) / (4 - 3*exp(2*x)).
%F a(n) = 1 + 3 * Sum_{k=1..n} 2^k * binomial(n,k) * a(n-k).
%o (PARI) a_vector(n) = my(v=vector(n+1)); for(i=0, n, v[i+1]=1+3*sum(j=1, i, 2^j*binomial(i, j)*v[i-j+1])); v;
%Y Cf. A080253, A337026, A368438.
%K nonn
%O 0,2
%A _Seiichi Manyama_, Dec 24 2023
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