OFFSET
0,1
COMMENTS
Average distance between two points chosen at random on two different faces of a unit cube.
LINKS
G. C. Greubel, Table of n, a(n) for n = 0..10000
D. H. Bailey, J. M. Borwein, V. Kapoor and E. Weisstein, Ten Problems in Experimental Mathematics
Eric Weisstein's World of Mathematics, Cube Line Picking
EXAMPLE
0.926390055...
MATHEMATICA
RealDigits[(4 + 17*Sqrt[2] - 6*Sqrt[3] - 7*Pi + 21*Log[1 + Sqrt[2]] + 42*Log[2 + Sqrt[3]])/75, 10, 10001][[1]] (* G. C. Greubel, Oct 01 2018 *)
PROG
(PARI) default(realprecision, 100); (4 + 17*sqrt(2) - 6*sqrt(3) - 7*Pi + 21*log(1 + sqrt(2)) + 42*log(2 + sqrt(3)))/75 \\ G. C. Greubel, Oct 01 2018
(Magma) SetDefaultRealField(RealField(100)); R:= RealField(); (4 + 17*Sqrt(2) - 6*Sqrt(3) - 7*Pi(R) + 21*Log(1 + Sqrt(2)) + 42*Log(2 + Sqrt(3)))/75; // G. C. Greubel, Oct 01 2018
CROSSREFS
KEYWORD
nonn,cons
AUTHOR
Eric W. Weisstein, Mar 16 2004
STATUS
approved