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A185197 Decimal expansion of 2/Pi^2. 8
2, 0, 2, 6, 4, 2, 3, 6, 7, 2, 8, 4, 6, 7, 5, 5, 4, 2, 8, 8, 7, 7, 5, 8, 9, 2, 6, 4, 1, 9, 4, 5, 5, 2, 7, 7, 8, 0, 8, 7, 1, 7, 5, 4, 9, 3, 4, 4, 4, 9, 3, 0, 9, 7, 6, 9, 1, 2, 1, 8, 0, 6, 3, 7, 8, 8, 3, 4, 6, 2, 4, 1, 9, 2, 4, 4, 7, 0, 8, 8, 2, 3, 8, 2, 4, 1, 8, 5, 4, 7, 8, 5, 1, 2, 4, 3, 6, 7, 5 (list; constant; graph; refs; listen; history; text; internal format)
OFFSET

0,1

COMMENTS

Asymptotic density of the even squarefree numbers (A039956). - Amiram Eldar, May 22 2020

REFERENCES

C. F. Gauss, Disquisitiones Arithmeticae, Yale, 1965; see p. 360.

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 0..3000

Index entries for transcendental numbers

FORMULA

Equals 1/(3*zeta(2)). - Michel Marcus, Jun 13 2017

Equals -Sum_{k>=1} mu(2*k)/(2*k)^2, where mu is the Möbius function (A008683). - Amiram Eldar, Jul 31 2020

EXAMPLE

.20264236728467554288775892641945527780871754934449309769121...

MATHEMATICA

RealDigits[2/\[Pi]^2, 10, 100][[1]] (* Harvey P. Dale, Mar 16 2011 *)

PROG

(PARI) 2/Pi^2 \\ Charles R Greathouse IV, Mar 25 2014

CROSSREFS

Cf. A008683, A013661, A039956.

Sequence in context: A320078 A136426 A325199 * A323845 A327116 A157491

Adjacent sequences: A185194 A185195 A185196 * A185198 A185199 A185200

KEYWORD

cons,nonn

AUTHOR

N. J. A. Sloane, Feb 19 2011

STATUS

approved

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Last modified March 24 11:39 EDT 2023. Contains 361479 sequences. (Running on oeis4.)