OFFSET
1,1
LINKS
Jonathan M. Borwein, Armin Straub, James Wan, and Wadim Zudilin, Densities of Short Uniform Random Walks p. 978, Canad. J. Math. 64(2012), 961-990.
Eric Weisstein's MathWorld, Clausen's Integral
FORMULA
W_3'(2) = 2 + (3/Pi)*Cl2(Pi/3) - 3*sqrt(3)/(2*Pi), where Cl2 is the Clausen function.
W_3'(2) = 2 + 3*W_3'(0) - 3*sqrt(3)/(2*Pi).
EXAMPLE
2.1422044985256634680139197847019650201206458017918000691935563806464998832...
MATHEMATICA
Clausen2[x_] := Im[PolyLog[2, Exp[x*I]]]; RealDigits[2 + (3/Pi)*Clausen2[Pi/3] - 3*Sqrt[3]/(2*Pi), 10, 105] // First
PROG
(PARI) 2 + 3*imag(polylog(2, exp(Pi*I/3)))/Pi - 3*sqrt(3)/2/Pi \\ Charles R Greathouse IV, Aug 27 2014
CROSSREFS
KEYWORD
AUTHOR
Jean-François Alcover, Jul 10 2014
STATUS
approved