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A005800
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Generalized Euler numbers of type 3^2n.
(Formerly M2188)
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0
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OFFSET
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0,2
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REFERENCES
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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) = (1/36^n) * Sum_{i=0..2*n} binomial(2*n, i) * A000364(n+i).
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MATHEMATICA
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a[n_] := Sum[Binomial[2n, i]Abs[EulerE[2(n+i)]], {i, 0, 2n}]/36^n
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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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