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A145433 Decimal expansion of Sum_{n>=1} (-1)^(n-1)*n/binomial(2n,n). 4
2, 7, 4, 4, 3, 2, 7, 1, 5, 2, 7, 7, 1, 2, 0, 3, 2, 3, 1, 1, 1, 1, 5, 4, 6, 5, 8, 6, 3, 6, 0, 4, 8, 4, 3, 4, 0, 3, 3, 9, 6, 5, 6, 5, 4, 6, 0, 3, 2, 2, 3, 1, 7, 2, 3, 8, 0, 5, 6, 0, 4, 8, 8, 3, 1, 9, 4, 0, 4, 8, 9, 7, 2, 3, 6, 8, 9, 0, 5, 5, 6, 9, 0, 8, 9, 1, 9, 2, 2, 1, 1, 7, 5 (list; constant; graph; refs; listen; history; text; internal format)
OFFSET

0,1

REFERENCES

Alexander Apelblat, Tables of Integrals and Series, Harri Deutsch, (1996), 4.1.39

LINKS

Table of n, a(n) for n=0..92.

Steven Finch, Central Binomial Coefficients [Cached copy, with permission of the author]

FORMULA

Equals 2*(15+2*A002163*A002390)/125.

EXAMPLE

0.274432715277120323...

MAPLE

6/25+4/125*5^(1/2)*ln(1/2+1/2*5^(1/2)) ;

MATHEMATICA

RealDigits[6/25 + 4*Sqrt[5]*Log[GoldenRatio]/125, 10, 93] // First (* Jean-Fran├žois Alcover, Oct 27 2014 *)

RealDigits[Hypergeometric2F1[2, 2, 3/2, -1/4]/2, 10, 93] // First (* Vaclav Kotesovec, Oct 27 2014 *)

CROSSREFS

Cf. A002163, A002390, A145434.

Sequence in context: A292819 A066766 A241517 * A055200 A323755 A093590

Adjacent sequences:  A145430 A145431 A145432 * A145434 A145435 A145436

KEYWORD

cons,easy,nonn

AUTHOR

R. J. Mathar, Feb 08 2009

STATUS

approved

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Last modified March 23 16:52 EDT 2019. Contains 321432 sequences. (Running on oeis4.)