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A099870
Decimal expansion of Sum_{n>0} 1/(n^log(n)).
8
2, 2, 3, 8, 1, 8, 1, 3, 0, 6, 7, 9, 6, 6, 9, 3, 0, 4, 3, 1, 8, 3, 1, 3, 6, 9, 9, 4, 1, 9, 9, 7, 1, 8, 0, 0, 9, 6, 1, 6, 1, 8, 1, 0, 8, 1, 7, 6, 5, 0, 0, 5, 4, 2, 2, 3, 9, 1, 5, 9, 0, 5, 0, 8, 1, 1, 6, 8, 2, 6, 9, 2, 7, 4, 6, 6, 2, 7, 0, 1, 2, 7, 7, 5, 7, 0, 5, 6, 4, 8, 4, 8, 3, 5, 3, 5, 5, 8, 1, 0, 8, 0, 1, 8, 6
OFFSET
1,1
COMMENTS
This series converges slowly. - Bernard Schott, May 23 2019
This series converges more slowly than Sum_{n>=0} 1/a^n for every a > 1 but faster than Sum_{n>=1} 1/n^p for every p > 1. - Jianing Song, Jul 25 2021
REFERENCES
J. M. Arnaudiès, P. Delezoide et H. Fraysse, Exercices résolus d'Analyse du cours de mathématiques - 2, Dunod, Exercice 9c, page 293.
LINKS
FORMULA
Equals Sum_{n>=1} 1/(n^log(n)).
EXAMPLE
2.23818130679669304318313699419971800961618108176500542239159050811...
MAPLE
evalf(sum(1/(n^log(n)), n=1..infinity), 110); \\ Bernard Schott, May 23 2019
MATHEMATICA
s = 0; Do[s = N[s + 1/n^Log[n], 256], {n, 10^7}]; RealDigits[s, 10, 111][[1]] (* Robert G. Wilson v, Nov 02 2004 *)
PROG
(PARI) default(realprecision, 35); sum(n=1, 50000, 1./(n^log(n)))
(PARI) sumpos(n=1, 1/(n^log(n))) \\ Michel Marcus, May 24 2019
(Magma) SetDefaultRealField(RealField(100)); [(&+[1/k^Log(k): k in [1..1000]])]; // G. C. Greubel, Nov 20 2018
(Sage) numerical_approx(sum(1/k^log(k) for k in [1..1000]), digits=100) # G. C. Greubel, Nov 20 2018
CROSSREFS
Sequence in context: A089543 A139073 A329955 * A221877 A110985 A153216
KEYWORD
nonn,cons
AUTHOR
Mark Hudson (mrmarkhudson(AT)hotmail.com), Oct 29 2004
EXTENSIONS
More terms from Robert G. Wilson v, Nov 02 2004
STATUS
approved