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Decimal expansion of the negated value of the digamma function at 4/5.
5

%I #13 Jun 02 2022 05:43:28

%S 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,

%T 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,

%U 1,2,0,7,3,8,5,6,8,4,0,0,4,3,0,6,3,7,6

%N Decimal expansion of the negated value of the digamma function at 4/5.

%H <a href="/index/Di#differential_equations">Index entries for sequences related to the digamma function</a>

%F Psi(4/5) = -gamma + Pi*sqrt(1+2/sqrt 5)/2 -5*log(5)*log((3+sqrt 5)/2)/4.

%e Psi(4/5) = -0.965008566706138459391297633...

%p -gamma+Pi*sqrt(1+2/sqrt(5))/2-5*log(5)/4-sqrt(5)/4*log(3/2+sqrt(5)/2) ; evalf(%) ;

%t RealDigits[ -PolyGamma[4/5], 10, 87] // First (* _Jean-François Alcover_, Feb 20 2013 *)

%o (PARI) -psi(4/5) \\ _Charles R Greathouse IV_, Nov 22 2011

%Y Cf. A020759, A047787, A020777, A200134-A200137.

%K cons,nonn

%O 0,1

%A _R. J. Mathar_, Nov 13 2011