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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 (list; constant; graph; refs; listen; history; text; internal format)
OFFSET

1,3

COMMENTS

BBP formula for Pi = 4*A145963 - (1/2)*A145960 - (1/2)*(A145961-A145962).

LINKS

Table of n, a(n) for n=1..100.

Eric Weisstein's World of Mathematics, BBP Formula

Index entries for transcendental numbers

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

Cf. A000796, A145961, A145962, A145963.

Sequence in context: A336382 A180317 A066654 * A205455 A338135 A259332

Adjacent sequences:  A145957 A145958 A145959 * A145961 A145962 A145963

KEYWORD

cons,nonn

AUTHOR

Artur Jasinski, Oct 25 2008

STATUS

approved

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Last modified March 9 03:03 EST 2021. Contains 341961 sequences. (Running on oeis4.)