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A093591
Decimal expansion of (12*Pi)/715.
4
0, 5, 2, 7, 2, 6, 0, 3, 0, 5, 4, 9, 7, 5, 8, 7, 6, 7, 6, 3, 8, 5, 3, 3, 8, 7, 4, 9, 6, 4, 1, 3, 1, 5, 1, 6, 9, 3, 7, 5, 7, 4, 8, 7, 1, 0, 3, 8, 4, 6, 3, 3, 1, 4, 4, 7, 7, 9, 0, 1, 1, 6, 7, 9, 8, 2, 7, 8, 8, 5, 2, 7, 0, 9, 8, 5, 0, 9, 8, 0, 1, 3, 7, 5, 5, 7, 5, 4, 0, 9, 6, 5, 6, 0, 9, 1, 4, 7, 5, 2, 6, 6, 8
OFFSET
0,2
COMMENTS
Mean volume of a tetrahedron formed by four random points in a unit ball.
Equals (4*Pi/15) times the probability (9/143) that 5 points independently and uniformly chosen in a ball are the vertices of a re-entrant (concave) polyhedron, i.e., one of the points falls within the tetrahedron formed by the other 4 points. It was calculated by the Czech physicist and mathematician Bohuslav Hostinský (1884 - 1951) in 1925. - Amiram Eldar, Aug 25 2020
REFERENCES
Bohuslav Hostinský, Sur les probabilités géométriques, Brno: Publications de la Faculté des sciences de l'Université Masaryk, 1925.
LINKS
Fernando Affentranger, The expected volume of a random polytope in a ball, Journal of Microscopy, Vol. 151, No. 3 (1988), pp. 277-287.
Herbert Solomon, Geometric Probability, Philadelphia, PA: SIAM, 1978, p. 124.
Eric Weisstein's World of Mathematics, Ball Tetrahedron Picking.
EXAMPLE
0.0527260305...
MATHEMATICA
RealDigits[12*Pi/715, 10, 100][[1]] (* Amiram Eldar, Aug 25 2020 *)
PROG
(PARI) 12*Pi/715 \\ Charles R Greathouse IV, Sep 30 2022
CROSSREFS
Cf. A093524.
Sequence in context: A343422 A214969 A372925 * A132800 A348432 A183167
KEYWORD
nonn,cons
AUTHOR
Eric W. Weisstein, Apr 02 2004
STATUS
approved