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A368273
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Expansion of e.g.f. exp(-2*x) / (1 + x*exp(x)).
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2
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1, -3, 8, -17, 20, 23, -50, -1185, 6648, 20143, -372646, 179111, 25378468, -126050121, -1849977930, 23353880527, 109161798512, -3986970251809, 6487865966386, 680166849412311, -5885809282265124, -109572316727641433, 2250978116175344846, 11909910338327490623
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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-2)^k / k!.
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PROG
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(PARI) a(n) = n!*sum(k=0, n, (-1)^(n-k)*(n-k-2)^k/k!);
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CROSSREFS
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KEYWORD
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sign
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AUTHOR
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STATUS
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approved
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