OFFSET
0,2
COMMENTS
The ratio of the volume of a regular tetrahedron to the volume of the circumscribed sphere. (The MathWorld link shows that the circumradius for a tetrahedron with side length a is a*sqrt(6)/4.)
LINKS
Frank Jackson and Eric W. Weisstein, Tetrahedron
FORMULA
EXAMPLE
0.122517532315953788780294777402882098...
MATHEMATICA
RealDigits[(2Sqrt[3])/(9Pi), 10, 120][[1]] (* Harvey P. Dale, Nov 17 2013 *)
PROG
(PARI) 2*3^(-3/2)/Pi
CROSSREFS
KEYWORD
cons,nonn
AUTHOR
Rick L. Shepherd, Sep 30 2009
STATUS
approved