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A065464 Decimal expansion of product(1 - (2p-1)/p^3), p prime >= 2). 5
4, 2, 8, 2, 4, 9, 5, 0, 5, 6, 7, 7, 0, 9, 4, 4, 4, 0, 2, 1, 8, 7, 6, 5, 7, 0, 7, 5, 8, 1, 8, 2, 3, 5, 4, 6, 1, 2, 1, 2, 9, 8, 5, 1, 3, 3, 5, 5, 9, 3, 6, 1, 4, 4, 0, 3, 1, 9, 0, 1, 3, 7, 9, 5, 3, 2, 1, 2, 3, 0, 5, 2, 1, 6, 1, 0, 8, 3, 0, 4, 4, 1, 0, 5, 3, 4, 8, 5, 1, 4, 5, 2, 4, 6, 8, 0, 6, 8 (list; constant; graph; refs; listen; history; text; internal format)
OFFSET

0,1

COMMENTS

Sum_{n <= x} A189021(n) ~ kx, where k is this constant. - Charles R Greathouse IV, Jan 24 2018

LINKS

Table of n, a(n) for n=0..97.

R. J. Mathar, Hardy-Littlewood constants embedded into infinite products..., arXiv:0903.2514 (2009) Equation (116).

G. Niklasch, Some number theoretical constants: 1000-digit values [Cached copy]

Eric Weisstein's World of Mathematics, Carefree Couple

FORMULA

Equals A065463 divided by A013661. - R. J. Mathar, Mar 22 2011

Equals A065473 divided by A065480. - R. J. Mathar, May 02 2019

EXAMPLE

0.428249505677094440218765707581823546...

MATHEMATICA

$MaxExtraPrecision = 800; digits = 98; terms = 2000; LR = Join[{0, 0}, LinearRecurrence[{-2, 0, 1}, {-2, 3, -6}, terms+10]]; r[n_Integer] := LR[[n]]; (6/Pi^2)*Exp[NSum[r[n]*(PrimeZetaP[n-1]/(n-1)), {n, 3, terms}, NSumTerms -> terms, WorkingPrecision -> digits+10, Method -> "AlternatingSigns"]] // RealDigits[#, 10, digits]& // First (* Jean-François Alcover, Apr 16 2016 *)

CROSSREFS

Cf. A078078.

Sequence in context: A112152 A211883 A083489 * A201400 A040015 A144926

Adjacent sequences:  A065461 A065462 A065463 * A065465 A065466 A065467

KEYWORD

cons,nonn

AUTHOR

N. J. A. Sloane, Nov 19 2001

STATUS

approved

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Last modified December 5 16:21 EST 2019. Contains 329753 sequences. (Running on oeis4.)