OFFSET
0,1
COMMENTS
This is also the expected distance from a randomly selected point in the unit sphere to its center. - Derek Orr, Jul 27 2014
FORMULA
Equals (sin(Pi/3))^2. - Michel Marcus, Sep 12 2020
Equals Sum_{k>=1} (zeta(2*k) - 1). - Amiram Eldar, May 24 2021
EXAMPLE
0.75000000000000000000000000000000000000000000000000000000000...
MATHEMATICA
RealDigits[3/4, 10, 128][[1]] (* Alonso del Arte, Feb 16 2015 *)
CROSSREFS
KEYWORD
AUTHOR
N. J. A. Sloane, Oct 30 2009
STATUS
approved