A256687 - OEIS

%I #10 Aug 27 2015 11:04:16

%S 9,7,0,2,6,7,2,5,4,0,0,0,1,8,6,3,7,3,6,0,8,4,4,2,6,7,6,4,8,9,4,2,1,5,

%T 3,1,8,5,7,7,5,5,0,5,9,9,8,2,1,9,1,2,4,8,6,4,3,4,9,7,4,8,4,7,9,4,5,5,

%U 5,1,2,2,7,0,3,0,0,8,6,5,3,6,3,3,8,6,9,9,7,0,5,3,0,5,7,1,2,1,9,9,3,7,4

%N Decimal expansion of the [negated] abscissa of the Gamma function local minimum in the interval [-10,-9].

%H Eric Weisstein's MathWorld, <a href="http://mathworld.wolfram.com/GammaFunction.html">Gamma Function</a>

%H Wikipedia, <a href="http://en.wikipedia.org/wiki/Particular_values_of_the_Gamma_function">Particular values of the Gamma Function</a>

%F Solution to PolyGamma(x) = 0 in the interval [-10,-9].

%e Gamma(-9.7026725400018637360844267648942153185775505998219124864...)

%e = 0.00000215741610452285054050313702063056774903546226316...

%t digits = 103; x0 = x /. FindRoot[PolyGamma[0, x] == 0, {x, -19/2}, WorkingPrecision -> digits + 5]; RealDigits[x0, 10, digits] // First

%Y Cf. A030169, A030171, A175472, A175473, A256681-A256686.

%K nonn,cons

%O 1,1

%A _Jean-François Alcover_, Apr 08 2015