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A065419
Decimal expansion of Hardy-Littlewood constant Product_{p prime >= 5} (1-(6*p^2-4*p+1)/(p-1)^4).
9
3, 0, 7, 4, 9, 4, 8, 7, 8, 7, 5, 8, 3, 2, 7, 0, 9, 3, 1, 2, 3, 3, 5, 4, 4, 8, 6, 0, 7, 1, 0, 7, 6, 8, 5, 3, 0, 2, 2, 1, 7, 8, 5, 1, 9, 9, 5, 0, 6, 6, 3, 9, 2, 8, 2, 9, 8, 3, 0, 8, 3, 9, 6, 2, 6, 0, 8, 8, 8, 7, 6, 7, 2, 9, 6, 6, 9, 2, 9, 9, 4, 8, 1, 3, 8, 4, 0, 2, 6, 4, 6, 8, 1, 7, 1, 4, 9, 3, 8
OFFSET
0,1
COMMENTS
For comparison: Product_{n>=5} (1-(6n^2-4n+1)/(n-1)^4) = 3/32. - R. J. Mathar, Feb 25 2009
REFERENCES
Steven R. Finch, Mathematical Constants, Encyclopedia of Mathematics and its Applications, vol. 94, Cambridge University Press, 2003, Section 2.1, p. 86.
EXAMPLE
0.30749487875832709312335448607107685302...
MATHEMATICA
$MaxExtraPrecision = 1000; digits = 99; terms = 1000; P[n_] := PrimeZetaP[ n] - 1/2^n - 1/3^n; LR = Join[{0, 0}, LinearRecurrence[{5, -4}, {-12, -60}, terms+10]]; r[n_Integer] := LR[[n]]; Exp[NSum[r[n]*P[n-1]/(n-1), {n, 3, terms}, NSumTerms -> terms, WorkingPrecision -> digits+10]] // RealDigits[#, 10, digits]& // First (* Jean-François Alcover, Apr 17 2016 *)
PROG
(PARI) prodeulerrat(1-(6*p^2-4*p+1)/(p-1)^4, 1, 5) \\ Amiram Eldar, Mar 10 2021
CROSSREFS
KEYWORD
cons,nonn
AUTHOR
N. J. A. Sloane, Nov 15 2001
EXTENSIONS
A sign in the definition corrected by R. J. Mathar, Feb 25 2009
STATUS
approved