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A322887 Decimal expansion of the asymptotic mean value of the exponential abundancy index A051377(k)/k. 3
1, 1, 3, 6, 5, 7, 0, 9, 8, 7, 4, 9, 3, 6, 1, 3, 9, 0, 8, 6, 5, 2 (list; constant; graph; refs; listen; history; text; internal format)
OFFSET

1,3

COMMENTS

Lim_{n->oo} (1/n) * Sum_{k=1..n} esigma(k)/k, where esigma(k) is the sum of exponential divisors of k (A051377).

LINKS

Table of n, a(n) for n=1..22.

Peter Hagis, Jr., Some results concerning exponential divisors, International Journal of Mathematics and Mathematical Sciences, Vol. 11, No. 2, (1988), pp. 343-349.

FORMULA

Equals Product_{p prime} (1 + (1 - 1/p) * Sum_{k>=1} 1/(p^(3*k)-p^k)).

EXAMPLE

1.136570987493613908652...

CROSSREFS

Cf. A013661 (all divisors), A051377.

Sequence in context: A275925 A282581 A247581 * A175650 A272976 A113533

Adjacent sequences:  A322884 A322885 A322886 * A322888 A322889 A322890

KEYWORD

nonn,cons,more

AUTHOR

Amiram Eldar, Dec 29 2018

EXTENSIONS

a(7)-a(22) from Jon E. Schoenfield, Dec 30 2018

STATUS

approved

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Last modified October 15 01:40 EDT 2019. Contains 328025 sequences. (Running on oeis4.)