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A146482
Decimal expansion of Product_{q in A001358} (1-1/(q*(q-1))).
1
8, 3, 9, 0, 4, 2, 1, 5, 4, 2, 7, 4, 4, 6, 8, 6, 0, 0, 7, 6, 8, 4, 6, 2, 1, 1, 1, 1, 9, 4, 5, 4, 1, 2, 5, 4, 9, 2, 8, 3, 0, 7, 1, 6, 6, 7, 6, 0, 8, 8, 2, 7, 3, 3, 0, 0, 0
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
Sequence in context: A099724 A024568 A166202 * A019938 A170937 A058265
KEYWORD
nonn,cons,less
AUTHOR
R. J. Mathar, Feb 13 2009
STATUS
approved