OFFSET
1,2
LINKS
Jonathan M. Borwein and Armin Straub, Special Values of Generalized Log-sine Integrals, ISSAC '11: Proceedings of the 36th International Symposium on Symbolic and Algebraic Computation, 2011, pp. 43-50.
Armin Straub, A Mathematica package for evaluating log-sine integrals
FORMULA
-Integral_{0..2*Pi/3} log(3*sin(x/2))^2 dx = (1/162)*(-4*Pi^3 + 324*Im(PolyLog(3, 1 - (-1)^(2/3))) -
108*Pi*Log(3/2)^2 + 27*Pi*Log(3)^2 + 12*Sqrt(3)*Pi^2*Log(27/4) -
18*Sqrt(3)*Log(27/4)*PolyGamma(1, 2/3)). (This formula was suggested by Mathematica.)
EXAMPLE
-1.9403919820720596979364925591310637161191841878362545269432607629448...
MATHEMATICA
RealDigits[(1/162)*(-4*Pi^3 + 324*Im[PolyLog[3, 1 - (-1)^(2/3)]] -
108*Pi*Log[3/2]^2 + 27*Pi*Log[3]^2 + 12*Sqrt[3]*Pi^2*Log[27/4] -
18*Sqrt[3]*Log[27/4]*PolyGamma[1, 2/3])
, 10, 105] // First
CROSSREFS
KEYWORD
nonn,cons
AUTHOR
Detlef Meya, Dec 19 2024
STATUS
approved
