OFFSET
1,1
LINKS
Vincenzo Librandi, Table of n, a(n) for n = 1..5000
Ernst D. Krupnikov and K. S. Kolbig, Some special cases of the generalized hypergeometric function _{q+1}F_q, J. Comp. Appl. Math. 78 (1997) 79-95
Eric Weisstein's World of Mathematics, Gauss's Digamma Theorem.
Wikipedia, Digamma function: special values.
FORMULA
Psi(1/6) = -gamma -Pi*sqrt(3)/2 -3*log(3)/2 -2*log(2).
EXAMPLE
Psi(1/6) = -6.3321275053749147924249615748457777225904948...
MATHEMATICA
RealDigits[-PolyGamma[1/6], 10, 90][[1]]
PROG
(PARI) -psi(1/6)
(Maxima) fpprec:90; ev(bfloat(-psi[0](1/6)));
CROSSREFS
KEYWORD
AUTHOR
Bruno Berselli, Feb 21 2013
STATUS
approved