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A103983
Decimal expansion of average length of a line segment picked at random in a unit 4-cube.
6
7, 7, 7, 6, 6, 5, 6, 5, 3, 5, 8, 6, 2, 6, 7, 1, 1, 5, 3, 3, 7, 9, 3, 4, 0, 9, 4, 6, 1, 7, 8, 1, 9, 5, 0, 9, 9, 6, 2, 8, 8, 2, 7, 2, 4, 4, 1, 7, 1, 3, 3, 0, 5, 8, 0, 2, 3, 4, 4, 5, 9, 6, 4, 8, 6, 5, 0, 5, 7, 3, 5, 3, 1, 5, 9, 2, 6, 5, 4, 0, 1, 1, 4, 6, 1, 5, 1, 6, 5, 6, 8, 9, 3, 1, 6, 8, 1, 8, 8, 4, 6, 5
OFFSET
1,1
REFERENCES
Steven R. Finch, Mathematical Constants, Encyclopedia of Mathematics and its Applications, vol. 94, Cambridge University Press, 2003, Section 8.1, p. 480.
LINKS
Eric Weisstein's World of Mathematics, Hypercube Line Picking.
FORMULA
(-644 + 438*sqrt(2) + 288*sqrt(3) + 1344*Catalan + 12*Pi(-16 + 7(-8 + 9*sqrt(2))*Pi) - 2448*sqrt(2)*arccot(2*sqrt(2)) + 3744*arccsch(sqrt(2)) + 270*arcsinh(1) - 3024*Im(PolyLog(2, i*(3 - 2*sqrt(2)))) + 1773*log(3) - 189*sqrt(2)*(PolyGamma(1, 1/8) + PolyGamma(1, 3/8)) + 84*(PolyGamma(1, 1/12) + PolyGamma(1, 5/12)) + 6048*i(PolyLog(2, (1/2 - i/2)*(-2 + sqrt(2))) - PolyLog)2, (1/2 + i/2)*(-2 + sqrt(2)))) + 6048*i(PolyLog(2, i*(1 - sqrt(2))) - PolyLog(2, i*(-1 + sqrt(2)))))/3780, where i=sqrt(-1). - Eric W. Weisstein, Mar 02 2005
EXAMPLE
0.777665653...
MATHEMATICA
A:= ( 0 - 3024*Im[PolyLog[2, I*(3 - 2*Sqrt[2])]] + 6048*I*(PolyLog[2, (1 - I)/2*(-2 + Sqrt[2])] - PolyLog[2, (1 + I)/2*(-2 + Sqrt[2])]) + 6048*I*(PolyLog[2, I*(1 - Sqrt[2])] - PolyLog[2, I*(-1 + Sqrt[2])]) )/3780;
B := (-644 + 438*Sqrt[2] + 288*Sqrt[3] + 1344*Catalan + 12*Pi*(-16 + 7*(-8 + 9*Sqrt[2])*Pi) - 2448*Sqrt[2]*ArcCot[2*Sqrt[2]] + 3744*ArcCsch[Sqrt[2]] + 270*ArcSinh[1] + 1773*Log[3] - 189*Sqrt[2]*(PolyGamma[1, 1/8] + PolyGamma[1, 3/8]) + 84*(PolyGamma[1, 1/12] + PolyGamma[1, 5/12]))/3780;
RealDigits[Re[A] + B, 10, 50][[1]] (* G. C. Greubel, Jan 11 2017 *)
CROSSREFS
KEYWORD
nonn,cons,changed
AUTHOR
Eric W. Weisstein, Feb 24 2005
STATUS
approved