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A145960
Decimal expansion of 2*log(5/3) used in BBP Pi formula.
4
1, 0, 2, 1, 6, 5, 1, 2, 4, 7, 5, 3, 1, 9, 8, 1, 3, 6, 6, 4, 1, 1, 0, 2, 8, 1, 9, 2, 6, 0, 7, 3, 2, 3, 8, 6, 9, 7, 5, 6, 2, 2, 1, 5, 9, 2, 8, 9, 1, 5, 3, 6, 5, 4, 0, 3, 5, 5, 9, 0, 7, 1, 1, 5, 6, 7, 3, 3, 6, 9, 3, 8, 8, 9, 7, 8, 0, 9, 7, 5, 9, 5, 5, 1, 3, 0, 3, 6, 2, 4, 6, 5, 5, 8, 8, 9, 5, 0, 4, 4
OFFSET
1,3
COMMENTS
BBP formula for Pi = 4*A145963 - (1/2)*A145960 - (1/2)*(A145961-A145962).
FORMULA
Equals 2*log(5/3) = 2*(log(5)-log(3)) = 2*(A016628 - A002391) = log(25/9) = 4*arctanh(1/4).
Equals Hypergeometric2F1(1, 1/2, 3/2, 1/16).
Equals Sum_{k>=0} (1/16)^k*(1/(2k+1)).
EXAMPLE
1.021651247531981366411...
MATHEMATICA
First[RealDigits[2 Log[5/3], 10, 100]]
PROG
(PARI) 2*log(5/3) \\ Michel Marcus, Apr 05 2015
CROSSREFS
KEYWORD
cons,nonn
AUTHOR
Artur Jasinski, Oct 25 2008
STATUS
approved