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%I #19 Dec 15 2017 17:36:25
%S 1,4,15,42,121,336,930,2548,6937,0,51322,0,379097,0,2801205,0,
%T 20698345,56264090,152941920,0,0,0,8350344420,0,61701166395,0,
%U 455913379395,1239301050694,3368769533660,0,24892027072619,0,183928584450999,0,0,0
%N Least m such that the average number of divisors of all integers from 1 to m equals n, or 0 if no such number exists.
%C "In 1838 Lejeune Dirichlet (1805-1859) proved that (1/n)*sum_{r=1..n} #(divisors(r)), the average number of divisors of all integers from 1 to n, approaches ln n + 2gamma - 1 as n increases." [Havil]
%C a(n+1)/a(n) ~ e. - _Robert G. Wilson v_
%D Julian Havil, "Gamma: Exploring Euler's Constant", Princeton University Press, Princeton and Oxford, pp. 112-113, 2003.
%H Donovan Johnson, <a href="/A085567/b085567.txt">Table of n, a(n) for n = 1..40</a>
%e a(2) = 4 because (1/4)*(1+2+2+3) = 2.
%Y Cf. A050226, A057494, A085829.
%K nonn
%O 1,2
%A _Jason Earls_, Jul 06 2003
%E Edited and extended by _Robert G. Wilson v_, Jul 07 2003
%E Corrected by _Rick L. Shepherd_, Aug 28 2003
%E Missing terms a(16)-a(17) and a(20)-a(29) added by _Donovan Johnson_, Dec 21 2008
%E a(30)-a(36) from _Donovan Johnson_, Jul 20 2011
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