A146487 - OEIS

A146487

Decimal expansion of Product_{q in A014612} (1-1/(q^2*(q-1))).

9, 9, 6, 5, 9, 8, 9, 2, 7, 4, 8, 0, 2, 4, 1, 2, 7, 3, 4, 1, 9, 1, 5, 9, 0, 4, 6, 3, 2, 9, 8, 9, 4, 6, 9, 2, 2, 9, 1, 0, 1, 0, 3, 9, 1, 0, 1, 1, 7, 8, 3, 8, 2, 0, 6, 5, 8

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OFFSET

0,1

COMMENTS

3-almost prime analog of A065414.

LINKS

Table of n, a(n) for n=0..56.

R. J. Mathar, Hardy-Littlewood constants embedded into infinite products over all positive integers, arXiv:0903.2514 [math.NT], table 3 at r=2, k=3. [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_3(s)/j at r=2, where P_k(s) are the k-almost prime zeta functions of arXiv:0803.0900.

EXAMPLE

0.99659892748024127.. = (1-1/448)*(1-1/1584)*(1-1/5508)*(1-1/7600)*..

CROSSREFS

Sequence in context: A262823 A157293 A346445 * A346442 A195790 A346444

Adjacent sequences: A146484 A146485 A146486 * A146488 A146489 A146490

KEYWORD

nonn,cons,less

AUTHOR

R. J. Mathar, Feb 13 2009

STATUS

approved