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A072973
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Denominator of b(n) = (50*n-6)/C(3n,n)/2^n.
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1
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1, 3, 30, 14, 3960, 24024, 28288, 1860480, 94140288, 199971200, 1183311360, 12386350080, 284826214400, 2376389615616, 433030996623360, 15188999733248, 73886889202384896, 484018391833804800, 4234776786964971520
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OFFSET
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0,2
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COMMENTS
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A powerful series to compute Pi via the Beta method. Proved first by Almkvist, Krattenthaler, Petersson (2001).
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LINKS
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FORMULA
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sum ( k>=0, b(k)) = Pi
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PROG
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(PARI) a(n)=denominator((50*n-6)/binomial(3*n, n)/2^n)
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CROSSREFS
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KEYWORD
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easy,frac,nonn
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AUTHOR
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STATUS
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approved
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