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A136636
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a(n) = n * C(2*3^(n-1), n) for n>=1.
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4
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2, 30, 2448, 1265004, 4368213360, 106458751541142, 19173684851378353296, 26413015283743616538733008, 285290979402099025600644272168880, 24601033850235942230699563821233785600080
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OFFSET
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1,1
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COMMENTS
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Equals column 1 of triangle A136635.
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LINKS
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FORMULA
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MAPLE
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MATHEMATICA
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PROG
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(PARI) {a(n)=n*binomial(2*3^(n-1), 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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STATUS
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approved
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