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%I #12 Jun 02 2022 05:41:52
%S 2,5,6,1,3,8,4,5,4,4,5,8,5,1,1,6,1,4,5,7,3,0,6,7,5,4,8,2,0,4,7,5,2,8,
%T 4,5,5,8,2,6,3,6,1,0,9,6,5,1,0,8,1,0,1,5,7,2,3,3,9,5,3,6,7,5,2,1,2,6,
%U 1,1,0,4,2,9,3,0,5,4,1,3,8,3,9,7
%N Decimal expansion of the negated value of the digamma function at 2/5.
%H <a href="/index/Di#differential_equations">Index entries for sequences related to the digamma function</a>
%F Psi(2/5) = -gamma -Pi*sqrt(1-2/sqrt 5)/2 -5*log(5)/4 +sqrt(5)*log((3+sqrt 5)/2)/4.
%e Psi(2/5) = -2.5613845445851161457306754820475...
%p -gamma-Pi*sqrt(1-2/sqrt(5))/2-5*log(5)/4+sqrt(5)*log((3+sqrt(5))/2)/4 ; evalf(%) ;
%t RealDigits[ PolyGamma[2/5], 10, 84] // First (* _Jean-François Alcover_, Feb 21 2013 *)
%o (PARI) -psi(2/5) \\ _Charles R Greathouse IV_, Jul 19 2013
%Y Cf. A020759, A020777, A047787, A200064, A200135-A200138.
%K cons,nonn
%O 1,1
%A _R. J. Mathar_, Nov 13 2011