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A395018
Decimal expansion of the mode of the distribution of distances between two points in the interior of a unit cube.
3
6, 7, 5, 2, 3, 0, 7, 5, 1, 9, 9, 1, 2, 6, 4, 2, 4, 4, 6, 3, 3, 1, 9, 6, 9, 0, 0, 7, 7, 4, 7, 5, 4, 3, 3, 4, 3, 1, 2, 5, 6, 5, 5, 2, 5, 6, 0, 8, 9, 1, 2, 7, 6, 6, 7, 6, 7, 5, 5, 4, 6, 7, 0, 5, 5, 6, 6, 8, 5, 6, 8, 2, 5, 1, 9, 1, 5, 2, 6, 8, 6, 4, 9, 6, 2, 1, 0, 1, 4, 7, 9, 7, 7, 0, 9, 3, 3, 1, 4, 8, 1, 3, 3, 7, 7
OFFSET
0,1
COMMENTS
The second of the 4 roots of 5*x^4 - 32*x^3 + 18*Pi*x^2 - 8*Pi*x = 0.
LINKS
Arak M. Mathai, Peter Moschopoulos, and Giorgio Pederzoli, Distance between random points in a cube, Statistica, Vol. 59, No. 1 (1999), pp. 61-81; ResearchGate link.
Eric Weisstein's World of Mathematics, Cube Line Picking.
EXAMPLE
0.675230751991264244633196900774754334312565525608912...
MATHEMATICA
RealDigits[x /. FindRoot[5*x^4 - 32*x^3 + 18*Pi*x^2 - 8*Pi*x, {x, 1/2}, WorkingPrecision -> 120]][[1]]
PROG
(PARI) solve(x = 1/2, 1, 5*x^4 - 32*x^3 + 18*Pi*x^2 - 8*Pi*x)
CROSSREFS
Cf. A073012 (mean), A395017 (median), A394605 (disk), A394607 (square), A395019 (ball), A395016.
Sequence in context: A332396 A100124 A355336 * A390931 A190648 A201519
KEYWORD
nonn,cons
AUTHOR
Amiram Eldar, Apr 10 2026
STATUS
approved