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%I #52 Nov 16 2024 06:30:21
%S 9,5,5,9,2,3,0,1,5,8,6,1,9,0,2,3,7,6,8,8,4,0,6,5,3,8,6,7,0,9,8,7,0,0,
%T 7,4,6,7,7,1,5,9,4,3,1,6,5,4,5,6,8,6,8,8,3,2,8,0,5,8,9,4,9,0,1,8,1,7,
%U 2,8,7,0,1,5,5,2,2,9,2,5,7,1,0,3,5,7,2,0,0,5,5,9,1,1,6,4,4,0,3,5,2,3,0,1,2,9,3,3,4,7,1,7,1,5,8,0,1,2,2,4,3,6,3,9,8,9,3,3,8,8,1,2,0,3,8,6,6,0,1,3,2,8,6,3,2,6,7,5,2,0,6,6,3,5,8,0,2,7,1,7,9,6,0
%N Decimal expansion of Toth's constant (or digits of the density of the exponentially squarefree numbers).
%H Vladimir Shevelev, <a href="http://arxiv.org/abs/1602.04244">A fast computation of density of exponentially S-numbers</a>, arXiv:1602.04244 [math.NT], 2016.
%H Laszlo Tóth, <a href="http://ac.inf.elte.hu/Vol_027_2007/155.pdf">On certain arithmetic functions involving exponential divisors, II.</a>, Annales Univ. Sci. Budapest., Sect. Comp., 27 (2007), 155-166.
%F Equals Product_{prime p} (1+Sum_{j>=4} (mu(j)^2 - mu(j-1)^2)/p^j), where mu(n) is the Möbius function.
%e 0.95592301586190237688406538670987007467715943165456868832805...
%Y Density of A209061.
%K nonn,cons
%O 0,1
%A _Juan Arias-de-Reyna_, Sep 19 2015