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Expansion of e.g.f. 1/(2 + x - exp(2*x)).
3

%I #8 Dec 02 2023 08:12:59

%S 1,1,6,38,344,3832,51408,803952,14371456,289005440,6457624832,

%T 158719896832,4255775425536,123619815742464,3867071262472192,

%U 129610289219999744,4633674344869756928,176011269522607144960,7079115958438736363520

%N Expansion of e.g.f. 1/(2 + x - exp(2*x)).

%F a(0) = 1; a(n) = -n * a(n-1) + Sum_{k=1..n} 2^k * binomial(n,k) * a(n-k).

%o (PARI) a_vector(n) = my(v=vector(n+1)); v[1]=1; for(i=1, n, v[i+1]=-i*v[i]+sum(j=1, i, 2^j*binomial(i, j)*v[i-j+1])); v;

%Y Cf. A032032, A367839, A367840.

%Y Cf. A367835.

%K nonn

%O 0,3

%A _Seiichi Manyama_, Dec 02 2023