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A145429
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Decimal expansion of Sum_{n > 0} n*(n!)^2/(2n)!.
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2
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1, 0, 6, 9, 7, 3, 3, 1, 9, 2, 0, 5, 2, 0, 4, 8, 4, 1, 1, 2, 4, 3, 1, 2, 8, 5, 0, 1, 6, 9, 8, 2, 5, 6, 8, 2, 9, 3, 9, 6, 4, 5, 9, 1, 6, 6, 2, 4, 2, 8, 3, 1, 2, 3, 9, 0, 1, 5, 5, 2, 9, 9, 8, 5, 6, 4, 1, 8, 0, 5, 1, 5, 1, 3, 6, 1, 4, 1, 1, 9, 7, 4, 1, 5, 2, 0, 2, 7, 7, 7, 5, 1, 5
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OFFSET
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1,3
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COMMENTS
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Also, decimal expansion of Sum_{n >= 0) n/binomial(2*n, n). - Bruno Berselli, Sep 14 2015
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REFERENCES
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Alexander Apelblat, Tables of Integrals and Series, Harri Deutsch, (1996), 4.1.35.
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LINKS
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FORMULA
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Equals 2/3 + 2*Pi/(9*sqrt(3)).
Equals 1 + Integral_{x>=1} 1/(x^2 + x + 1)^2 dx. (End)
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EXAMPLE
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1.069733192052..
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MAPLE
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2/3+2/27*Pi*3^(1/2) ;
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MATHEMATICA
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RealDigits[2/3 + 2*Pi/(9*Sqrt[3]), 10, 100][[1]] (* Amiram Eldar, Nov 16 2021 *)
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CROSSREFS
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Cf. A010722 (decimal expansion of Sum_{n >= 0} n/binomial(2*n+1, n)).
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KEYWORD
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AUTHOR
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STATUS
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approved
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