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A053490
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E.g.f.: (1-x)^(-3x).
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2
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1, 0, 6, 9, 132, 630, 6642, 55440, 608976, 6790392, 85413960, 1145077560, 16600386888, 256806229680, 4233767671728, 74015194485960, 1368023697469440, 26649263762049600, 545697922821501888, 11717708270380421760, 263276186128105633920
(list; graph; refs; listen; history; internal format)
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OFFSET
| 0,3
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REFERENCES
| R. P. Stanley, Enumerative Combinatorics, Cambridge, Vol. 2, 1999; see Example 5.2.3.
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FORMULA
| a(n) = (-1)^n*Sum_{k=0..floor(n/2)} 3^k*binomial(n, k)*k!*Stirling1(n-k, k). - Vladeta Jovovic (vladeta(AT)eunet.rs), Dec 19 2004
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CROSSREFS
| A007113, A053489.
Sequence in context: A121233 A156180 A191011 * A061110 A110460 A159190
Adjacent sequences: A053487 A053488 A053489 * A053491 A053492 A053493
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KEYWORD
| nonn
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AUTHOR
| N. J. A. Sloane (njas(AT)research.att.com), Jan 15 2000
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