OFFSET
0,1
FORMULA
Psi(4/5) = -gamma + Pi*sqrt(1+2/sqrt 5)/2 -5*log(5)*log((3+sqrt 5)/2)/4.
EXAMPLE
Psi(4/5) = -0.965008566706138459391297633...
MAPLE
-gamma+Pi*sqrt(1+2/sqrt(5))/2-5*log(5)/4-sqrt(5)/4*log(3/2+sqrt(5)/2) ; evalf(%) ;
MATHEMATICA
RealDigits[ -PolyGamma[4/5], 10, 87] // First (* Jean-François Alcover, Feb 20 2013 *)
PROG
(PARI) -psi(4/5) \\ Charles R Greathouse IV, Nov 22 2011
CROSSREFS
KEYWORD
cons,nonn
AUTHOR
R. J. Mathar, Nov 13 2011
STATUS
approved