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A132037 Decimal expansion of Product_{k>0} (1-1/9^k). 11
8, 7, 6, 5, 6, 0, 3, 5, 4, 0, 3, 5, 9, 6, 4, 2, 0, 5, 8, 3, 6, 0, 1, 9, 8, 3, 8, 4, 1, 7, 8, 6, 2, 0, 1, 0, 1, 0, 6, 6, 3, 5, 1, 0, 1, 1, 7, 4, 6, 7, 1, 8, 3, 3, 6, 1, 4, 9, 3, 5, 2, 8, 0, 1, 5, 8, 7, 0, 8, 5, 4, 2, 3, 1, 7, 1, 8, 2, 9, 9, 6, 9, 9, 0, 4, 4, 4, 7, 7, 7, 6, 9, 2, 0, 7, 9, 1, 9, 6, 4, 5, 0, 9 (list; constant; graph; refs; listen; history; text; internal format)
OFFSET

0,1

LINKS

Table of n, a(n) for n=0..102.

FORMULA

exp(-sum{n>0, sigma_1(n)/n*1/9^n})=exp(-sum{n>0, A000203(n)/n*1/9^n}).

Equals sum_{n>=0} A010815(n)/9^n. [From R. J. Mathar, Mar 04 2009]

EXAMPLE

0.8765603540359642058360198...

MATHEMATICA

digits = 103; NProduct[1-1/9^k, {k, 1, Infinity}, NProductFactors -> 100, WorkingPrecision -> digits+3] // N[#, digits+3]& // RealDigits[#, 10, digits]& // First (* Jean-Fran├žois Alcover, Feb 18 2014 *)

CROSSREFS

Cf. A027877, A048651, A100220, A132025, A132026, A132038, A098844, A067080, A000203.

Sequence in context: A194756 A132672 A212410 * A247095 A124597 A214023

Adjacent sequences:  A132034 A132035 A132036 * A132038 A132039 A132040

KEYWORD

nonn,cons

AUTHOR

Hieronymus Fischer, Aug 14 2007

STATUS

approved

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Last modified May 25 22:17 EDT 2019. Contains 323576 sequences. (Running on oeis4.)