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A206256 Decimal expansion of Product_{p prime} (1 - 3/p^2). 2
1, 2, 5, 4, 8, 6, 9, 8, 0, 9, 0, 5, 8, 0, 9, 2, 9, 8, 3, 3, 4, 4, 2, 7, 9, 9, 9, 0, 8, 9, 7, 5, 3, 5, 4, 0, 5 (list; constant; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

This is the probability that n, n+1, n+2 all are squarefree.

LINKS

Table of n, a(n) for n=0..36.

EXAMPLE

0.1254869809058...

MAPLE

# See A175640 using efact := 1-3/p^2 - R. J. Mathar, Mar 22 2012

CROSSREFS

Cf. A059956, A065474, A007675.

Sequence in context: A060710 A271853 A146101 * A093052 A081556 A187012

Adjacent sequences:  A206253 A206254 A206255 * A206257 A206258 A206259

KEYWORD

nonn,cons,more

AUTHOR

N. J. A. Sloane, Feb 05 2012, based on a posting by Warren Smith to the Math Fun Mailing List, Feb 04 2012

STATUS

approved

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Last modified August 26 01:23 EDT 2019. Contains 326324 sequences. (Running on oeis4.)