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A368272
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Expansion of e.g.f. exp(-x) / (1 + x*exp(x)).
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2
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1, -2, 3, -1, -11, 19, 151, -799, -2295, 37367, -16469, -2114531, 9695533, 132142451, -1556927553, -6822608311, 234527654161, -360436983569, -35798255259821, 294290464165685, 5217729367883061, -102317187098688661, -517822188623299097, 31412148276241662049
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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(n) = n! * Sum_{k=0..n} (-1)^(n-k) * (n-k-1)^k / k!.
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PROG
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(PARI) a(n) = n!*sum(k=0, n, (-1)^(n-k)*(n-k-1)^k/k!);
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CROSSREFS
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KEYWORD
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sign,easy
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AUTHOR
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STATUS
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approved
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