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A112099
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Numerator of Sum_{i=1..n} 1/(i*C(2*i,i)).
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3
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0, 1, 7, 3, 169, 1523, 133, 72623, 87149, 823077, 15638477, 46915441, 13834041, 224803169, 6936783521, 5587964507, 4157445593923, 12472336782289, 170187831339, 71785227258967, 153825486983593, 4905323862699739, 21820233734078929, 5695081004594650211
(list; graph; refs; listen; history; internal format)
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OFFSET
| 0,3
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REFERENCES
| C. Elsner, On recurrence formulae for sums involving binomial coefficients, Fib. Q., 43 (No. 1, 2005), 31-45.
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FORMULA
| Sum_{i=1..infinity} 1/(i*C(2*i, i)) = Pi sqrt(3)/9.
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EXAMPLE
| 0, 1/2, 7/12, 3/5, 169/280, 1523/2520, 133/220, 72623/120120, 87149/144144, .... -> Pi sqrt(3)/9.
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CROSSREFS
| Cf. A112100, A112102, A112103, A130549, A130550, A134805.
Sequence in context: A003723 A054471 A086453 * A013324 A110792 A175998
Adjacent sequences: A112096 A112097 A112098 * A112100 A112101 A112102
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KEYWORD
| nonn,frac
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AUTHOR
| N. J. A. Sloane (njas(AT)research.att.com), Nov 30 2005
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EXTENSIONS
| Definition corrected by Wolfdieter Lang, Oct 07 2008
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