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A078087
Continued fraction expansion of Product_{p prime} (1 - 1/(p^2*(p+1))).
1
0, 1, 7, 2, 3, 1, 1, 1, 7, 1, 1, 6, 1, 5, 1, 1, 3, 2, 1, 1, 3, 2, 1, 1, 1, 1, 13, 1, 16, 1, 1, 16, 1, 80, 1, 1, 1, 1, 7, 5, 1, 4, 1, 33, 3, 8, 1, 8, 1, 16, 11, 1, 2, 6, 1, 19, 1, 12, 5, 11, 1, 7, 5, 1, 1, 1, 2, 5, 1, 4, 1, 3, 4, 4, 4, 1, 11, 1, 2, 5, 4, 12, 3, 1, 4, 1, 3, 1, 168, 1, 4, 1, 1
OFFSET
0,3
MATHEMATICA
digits = 93;
$MaxExtraPrecision = 4 digits;
terms = 4 digits;
LR = Join[{0, 0, 0}, LinearRecurrence[{-2, -1, 1, 1}, {-3, 4, -5, 3}, terms + 10]];
r[n_Integer] := LR[[n]];
c = Exp[NSum[r[n] PrimeZetaP[n - 1]/(n - 1), {n, 4, terms}, NSumTerms -> terms, WorkingPrecision -> digits + 10]];
ContinuedFraction[c][[;; digits]] (* Jean-François Alcover, Aug 01 2019 *)
PROG
(PARI) contfrac(prodeulerrat(1 - 1/(p^2*(p+1)))) \\ Amiram Eldar, Mar 14 2021
CROSSREFS
Cf. A065465 (decimal expansion).
Sequence in context: A126341 A324788 A354640 * A176976 A291361 A198607
KEYWORD
nonn,cofr
AUTHOR
Benoit Cloitre, Dec 02 2002
EXTENSIONS
Offset changed by Andrew Howroyd, Jul 05 2024
STATUS
approved