OFFSET
0,1
COMMENTS
Semiprime analog of A005596.
LINKS
R. J. Mathar, Hardy-Littlewood constants embedded into infinite products over all positive integers, arXiv:0903.2514 [math.NT], Table 3 third line. [From R. J. Mathar, Mar 28 2009]
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=1, where P_k(s) are the k-almost prime zeta functions of arXiv:0803.0900.
EXAMPLE
0.839042154274468600768... = (1-1/12)*(1-1/30)*(1-1/72)*(1-1/90)*(1-1/182)*..
CROSSREFS
KEYWORD
AUTHOR
R. J. Mathar, Feb 13 2009
STATUS
approved