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A360935
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Expansion of e.g.f. Sum_{k>=0} exp((k^k - 1)*x) * x^k/k!.
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2
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1, 1, 1, 10, 159, 8306, 1346855, 801620870, 2064941077199, 20691706495244482, 1137052204448926181679, 255128692791512749880418782, 348784909594653094321340422905383, 2262992285674206001784964011734257207938
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OFFSET
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0,4
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LINKS
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FORMULA
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G.f.: Sum_{k>=0} x^k/(1 - (k^k - 1)*x)^(k+1).
a(n) = Sum_{k=0..n} (k^k - 1)^(n-k) * binomial(n,k).
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PROG
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(PARI) my(N=20, x='x+O('x^N)); Vec(serlaplace(1+x+sum(k=2, N, exp((k^k-1)*x)*x^k/k!)))
(PARI) my(N=20, x='x+O('x^N)); Vec(sum(k=0, N, x^k/(1-(k^k-1)*x)^(k+1)))
(PARI) a(n) = sum(k=0, n, (k^k-1)^(n-k)*binomial(n, k));
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CROSSREFS
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KEYWORD
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nonn,easy
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AUTHOR
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STATUS
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approved
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