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A065466
Decimal expansion of Product_{p prime} (1 - 1/(p^3*(p+1))).
4
9, 4, 7, 7, 3, 3, 2, 6, 2, 1, 4, 3, 6, 7, 5, 3, 7, 5, 9, 3, 9, 5, 2, 1, 5, 3, 7, 6, 5, 4, 1, 8, 9, 6, 1, 3, 0, 3, 3, 6, 3, 1, 6, 3, 2, 3, 1, 7, 4, 1, 3, 8, 5, 2, 8, 2, 8, 7, 5, 1, 0, 8, 8, 9, 0, 9, 3, 2, 3, 3, 2, 9, 4, 7, 8, 9, 8, 9, 9, 8, 7, 1, 3, 9, 5, 3, 4, 4, 1, 2, 8, 2, 6, 1, 3, 4, 4, 9
OFFSET
0,1
EXAMPLE
0.947733262143675375939521537654189613...
MATHEMATICA
$MaxExtraPrecision = 600; digits = 98; terms = 600; P[n_] := PrimeZetaP[n]; LR = Join[{0, 0, 0, 0}, LinearRecurrence[{-2, -1, 0, 1, 1}, {-4, 5, -6, 7, -12}, 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 18 2016 *)
PROG
(PARI) prodeulerrat(1 - 1/(p^3*(p+1))) \\ Amiram Eldar, Mar 13 2021
CROSSREFS
Cf. A078085.
Sequence in context: A021841 A176515 A087017 * A122790 A288241 A199665
KEYWORD
cons,nonn
AUTHOR
N. J. A. Sloane, Nov 19 2001
STATUS
approved