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A368266
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Expansion of e.g.f. exp(-2*x) / (1 - x*exp(x)).
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1
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1, -1, 4, 1, 60, 393, 4498, 54689, 773384, 12268369, 216328614, 4195769433, 88776964444, 2034936319817, 50232646818890, 1328570248040497, 37481046375146640, 1123486426007081505, 35657224567565828302, 1194561018775753556777, 42125545306641497600036
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OFFSET
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0,3
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LINKS
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FORMULA
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a(n) = n! * Sum_{k=0..n} (n-k-2)^k / k!.
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PROG
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(PARI) a(n) = n!*sum(k=0, n, (n-k-2)^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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