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A322887 Decimal expansion of the asymptotic mean value of the exponential abundancy index A051377(k)/k. 1

%I

%S 1,1,3,6,5,7,0,9,8,7,4,9,3,6,1,3,9,0,8,6,5,2

%N Decimal expansion of the asymptotic mean value of the exponential abundancy index A051377(k)/k.

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

%H Peter Hagis, Jr., <a href="http://dx.doi.org/10.1155/S0161171288000407">Some results concerning exponential divisors</a>, International Journal of Mathematics and Mathematical Sciences, Vol. 11, No. 2, (1988), pp. 343-349.

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

%e 1.136570987493613908652...

%Y Cf. A013661 (all divisors), A051377.

%K nonn,cons,more

%O 1,3

%A _Amiram Eldar_, Dec 29 2018

%E a(7)-a(22) from _Jon E. Schoenfield_, Dec 30 2018

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Last modified April 22 04:04 EDT 2019. Contains 322329 sequences. (Running on oeis4.)