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%I #12 Mar 06 2017 02:01:13
%S 3,3,0,0,9,8,0,3,5,3,9,0,0,2,2,1
%N Decimal expansion of the density of integers that are divisible by the square of their least prime factor.
%F 1/2^2 + (1/2)/3^2 + (1/2)*(2/3)/5^2 + (1/2)*(2/3)*(4/5)/7^2 + (1/2)*(2/3)*(4/5)*(6/7)/11^2 + ....
%e 0.3300980353900221...
%o (PARI) primezeta(s)=my(t=s*log(2),iter=lambertw(t/eps())\t); sum(k=1,iter, moebius(k)/k*log(abs(zeta(k*s))))
%o Pz=primezeta(2); s=0; t=1.; forprime(p=2,1e10, Pz-=1/p^2; s+=t/p^2; t*=1-1/p); s+t*Pz
%Y Cf. A283050.
%K nonn,cons,more
%O 0,1
%A _Charles R Greathouse IV_ and _Michel Marcus_, Feb 28 2017