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%I #7 Oct 29 2021 09:06:27
%S 1,1,0,2,8,4,5,3,0,3,7,7,8,6,2,7,0,5,8,5,9,3,0,5,1,8,8,8,7,4,7,3,5,5,
%T 9,6,9,5,7,7,3,3,3,5,5,9,6,5,1,5,8,9,3,4,1,3,4,8,2,4,0,3,8,2,4,6,5,9,
%U 7,4,4,1,0,2,3,0,9,9,6,0,5,2,1,7,7,7,5,4,1,3,4,6,1,3,5,1,1,8,6,6,9,1,9,5,1
%N Decimal expansion of the average length of a chord in a unit cube defined by the intersection of the surface with a straight line passing through 2 points uniformly and independently chosen at random in the interior of the cube.
%H Rodney Coleman, <a href="https://www.jstor.org/stable/3212012">Random paths through convex bodies</a>, Journal of Applied Probability, Vol. 6, No. 2 (1969), pp. 430-441; <a href="https://doi.org/10.2307/3212012">alternative link</a>; <a href="https://www.researchgate.net/publication/268246373_Random_Paths_Through_Convex_Bodies">author's link</a>.
%F Equals 4/63 - Pi/9 + 17*sqrt(2)/63 - 2*sqrt(3)/21 + log(1+sqrt(2))/3 + 2*log(2+sqrt(3))/3.
%e 1.10284530377862705859305188874735596957733355965158...
%t RealDigits[4/63 - Pi/9 + 17*Sqrt[2]/63 - 2*Sqrt[3]/21 + Log[1+Sqrt[2]]/3 + 2*Log[2+Sqrt[3]]/3, 10, 100][[1]]
%o (PARI) 4/63 - Pi/9 + 17*sqrt(2)/63 - 2*sqrt(3)/21 + log(1+sqrt(2))/3 + 2*log(2+sqrt(3))/3 \\ _Michel Marcus_, Oct 29 2021
%Y Cf. A073012, A093066, A348680, A348681, A348682.
%K nonn,cons
%O 1,4
%A _Amiram Eldar_, Oct 29 2021