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A000559
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Generalized Stirling numbers of second kind.
(Formerly M4858 N2076)
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5
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1, 12, 110, 945, 8092, 70756, 638423, 5971350, 57996774, 585092607, 6128147610, 66579524648, 749542556193, 8733648533696, 105203108066962, 1308549777461505, 16787682400875456, 221901108871482760, 3018891886411332135, 42230736603244134242
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OFFSET
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3,2
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REFERENCES
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N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).
N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
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LINKS
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FORMULA
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a(n) = Sum_{k=0..n} Stirling2(n,k)*Stirling2(k,3).
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MATHEMATICA
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nn = 23; t = Range[0, nn]! CoefficientList[Series[1/6*(Exp[Exp[x] - 1] - 1)^3, {x, 0, nn}], x]; Drop[t, 3] (* T. D. Noe, Aug 10 2012 *)
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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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EXTENSIONS
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STATUS
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approved
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