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A146488 Decimal expansion of Product_{q in A014613} (1-1/(q^2*(q-1))). 1
9, 9, 9, 5, 9, 5, 2, 7, 8, 5, 8, 6, 5, 3, 5, 5, 3, 5, 6, 3, 7, 4, 5, 2, 4, 9, 3, 2, 4, 8, 3, 3, 6, 4, 5, 3, 0, 8, 3, 6, 5, 0, 6, 3, 2, 4, 1, 2, 6, 7, 4, 0, 4, 9, 8, 8, 7 (list; constant; graph; refs; listen; history; text; internal format)
OFFSET

0,1

COMMENTS

4-almost prime analog of A065414.

LINKS

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

FORMULA

The logarithm is -sum_{s>=2} sum_{j=1..floor[s/(1+r)]} binomial(s-r*j-1,j-1)*P_4(s)/j at r=2, where P_k(s) are the k-almost prime zeta functions of arXiv:0803.0900.

EXAMPLE

0.99959527858653553563... = (1-1/3840)*(1-1/13248)*(1-1/45360)*(1-1/62400)*..

CROSSREFS

Sequence in context: A111613 A111591 A258814 * A051557 A146491 A112118

Adjacent sequences:  A146485 A146486 A146487 * A146489 A146490 A146491

KEYWORD

nonn,cons,less

AUTHOR

R. J. Mathar, Feb 13 2009

STATUS

approved

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Last modified February 29 07:24 EST 2020. Contains 332355 sequences. (Running on oeis4.)