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A354291
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Expansion of e.g.f. exp(f(x) - 1) where f(x) = 1/(4 - 3*exp(x)) = e.g.f. for A032033.
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3
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1, 3, 30, 435, 8211, 190056, 5196099, 163541055, 5815620696, 230350071189, 10048990989747, 478467217544322, 24678559536271581, 1370217125170670367, 81457311857722336614, 5160975525978898855143, 347090708803947931122807, 24690132231344937537382560
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OFFSET
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0,2
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LINKS
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FORMULA
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a(0) = 1; a(n) = Sum_{k=1..n} A032033(k) * binomial(n-1,k-1) * a(n-k).
a(n) = Sum_{k=0..n} 3^k * A000262(k) * Stirling2(n,k).
a(n) ~ exp(-7/8 - n + 1/(8*log(4/3)) + sqrt(n/log(4/3))) * n^(n - 1/4) / (2*log(4/3)^(n + 1/4)). - Vaclav Kotesovec, May 23 2022
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PROG
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(PARI) my(N=20, x='x+O('x^N)); Vec(serlaplace(exp(3*(exp(x)-1)/(4-3*exp(x)))))
(PARI) a_vector(n) = my(v=vector(n+1)); v[1]=1; for(i=1, n, v[i+1]=sum(j=1, i, sum(k=0, j, 3^k*k!*stirling(j, k, 2))*binomial(i-1, j-1)*v[i-j+1])); v;
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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