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A200138
Decimal expansion of the negated value of the digamma function at 4/5.
5
9, 6, 5, 0, 0, 8, 5, 6, 6, 7, 0, 6, 1, 3, 8, 4, 5, 9, 3, 9, 1, 2, 9, 7, 6, 3, 3, 1, 5, 6, 8, 3, 5, 4, 1, 9, 6, 3, 4, 1, 6, 0, 4, 8, 9, 6, 9, 5, 2, 2, 2, 8, 2, 9, 1, 0, 9, 8, 1, 0, 7, 9, 4, 2, 4, 4, 9, 6, 1, 2, 0, 7, 3, 8, 5, 6, 8, 4, 0, 0, 4, 3, 0, 6, 3, 7, 6
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