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A145432
Decimal expansion of sum_{n=1..inf} (-1)^(n-1)*2^n/binomial(2n,n).
0
5, 8, 6, 7, 8, 1, 9, 9, 8, 7, 6, 6, 9, 8, 2, 1, 1, 5, 8, 4, 3, 6, 9, 8, 0, 8, 4, 9, 6, 0, 1, 3, 5, 2, 7, 4, 7, 3, 3, 8, 7, 5, 9, 1, 0, 3, 1, 5, 7, 2, 5, 4, 7, 5, 6, 7, 3, 5, 2, 3, 5, 5, 6, 7, 5, 3, 3, 5, 1, 7, 0, 7, 5, 5, 1, 6, 3, 6, 9, 1, 7, 6, 7, 6, 1, 5, 2, 7, 8, 8, 2, 6, 6
OFFSET
0,1
REFERENCES
Alexander Apelblat, Tables of Integrals and Series, Harri Deutsch, (1996), 4.1.38
FORMULA
(1+log(2+sqrt(3))/sqrt(3))/3 .
EXAMPLE
0.58678199876...
MAPLE
1/3+1/9*ln(2+3^(1/2))*3^(1/2) ;
MATHEMATICA
RealDigits[Sum[(-1)^(n-1) 2^n/Binomial[2n, n], {n, \[Infinity]}], 10, 120][[1]] (* Harvey P. Dale, Apr 22 2022 *)
CROSSREFS
Sequence in context: A160043 A322633 A346443 * A335565 A365793 A070371
KEYWORD
cons,easy,nonn
AUTHOR
R. J. Mathar, Feb 08 2009
STATUS
approved