A283071 Decimal expansion of the density of integers that are divisible by the square of their least prime factor.

3, 3, 0, 0, 9, 8, 0, 3, 5, 3, 9, 0, 0, 2, 2, 1

Offset: 0

Author

Charles R Greathouse IV and Michel Marcus, Feb 28 2017

Keywords

• nonn
• cons
• more

Examples

			0.3300980353900221...
		

Crossrefs

Cf. A283050.

Programs

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))))
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

Formula

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 + ....