OFFSET
2,3
LINKS
Eric Weisstein's World of Mathematics, Digamma Function
Wikipedia, Digamma function
FORMULA
Psi(1/10) = -gamma - Pi*5^(1/4)*(sqrt(2 + sqrt(5))/2) - 2*log(2) - 5*log(5)/4 - 3*sqrt(5)*log((1 + sqrt(5))/2)/2, where gamma is the Euler-Mascheroni constant A001620.
Equals gamma - H(-9/10), H(z) the harmonic number. - Peter Luschny, Aug 22 2019
EXAMPLE
Equals 10.4237549404110767951682162190100254042916425624441889203263920841...
MAPLE
evalf(-Psi(1/10), 102);
MATHEMATICA
RealDigits[-PolyGamma[1/10], 10, 105][[1]]
PROG
(PARI) -psi(1/10)
CROSSREFS
KEYWORD
nonn,cons
AUTHOR
Vaclav Kotesovec, Aug 22 2019
STATUS
approved