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A348681
Decimal expansion of the average length of a chord in a unit square defined by the intersection of the perimeter with a straight line passing through 2 points uniformly and independently chosen at random in the interior of the square.
4
1, 0, 4, 2, 8, 1, 0, 8, 6, 6, 3, 2, 9, 4, 4, 1, 3, 5, 6, 6, 6, 1, 9, 6, 4, 7, 1, 3, 2, 1, 4, 4, 8, 7, 9, 4, 9, 8, 2, 8, 0, 6, 3, 1, 3, 5, 5, 5, 8, 0, 1, 6, 6, 8, 3, 5, 9, 2, 4, 2, 1, 0, 3, 7, 5, 0, 1, 0, 1, 5, 7, 8, 6, 6, 0, 9, 6, 3, 1, 6, 6, 3, 7, 3, 5, 8, 5, 6, 2, 6, 5, 8, 5, 0, 5, 2, 2, 9, 0, 4, 9, 3, 5, 8, 2
OFFSET
1,3
REFERENCES
A. M. Mathai, An introduction to geometrical probability: distributional aspects with applications, Amsterdam: Gordon and Breach, 1999, p. 221, ex. 2.3.7.
LINKS
Rodney Coleman, Random paths through convex bodies, Journal of Applied Probability, Vol. 6, No. 2 (1969), pp. 430-441; alternative link; author's link.
FORMULA
Equals (2/3) * (log(1 + sqrt(2)) + (2 + sqrt(2))/5).
EXAMPLE
1.04281086632944135666196471321448794982806313555801...
MATHEMATICA
RealDigits[(2/3) * (Log[1 + Sqrt[2]] + (2 + Sqrt[2])/5), 10, 100][[1]]
PROG
(PARI) (2/3) * (log(1 + sqrt(2)) + (2 + sqrt(2))/5) \\ Michel Marcus, Oct 29 2021
CROSSREFS
KEYWORD
nonn,cons
AUTHOR
Amiram Eldar, Oct 29 2021
STATUS
approved