OFFSET
0,1
COMMENTS
Semiprime analog of A065416.
FORMULA
The logarithm is -sum_{s>=2} sum_{j=1..floor[s/(1+r)]} binomial(s-r*j-1,j-1)*P_2(s)/j at r=4, where P_k(s) are the k-almost prime zeta functions of arXiv:0803.0900.
EXAMPLE
0.998509500607573754... = (1-1/768)*(1-1/6480)*(1-1/52488)*..
CROSSREFS
KEYWORD
AUTHOR
R. J. Mathar, Feb 13 2009
STATUS
approved