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A394608
Decimal expansion of the median of the distribution of distances between two points in a unit square.
6
5, 1, 2, 0, 0, 3, 2, 6, 9, 0, 8, 3, 3, 3, 3, 8, 8, 2, 1, 3, 1, 0, 8, 1, 1, 9, 9, 4, 7, 4, 7, 9, 3, 5, 4, 5, 1, 7, 9, 3, 9, 0, 9, 4, 4, 0, 6, 0, 4, 1, 5, 8, 9, 5, 5, 2, 6, 0, 5, 8, 2, 9, 0, 5, 6, 6, 9, 1, 2, 4, 7, 3, 9, 7, 6, 6, 0, 3, 0, 7, 3, 1, 0, 9, 8, 1, 4, 3, 3, 3, 3, 4, 4, 5, 4, 8, 6, 5, 8, 7, 7, 9, 3, 6, 0, 4
OFFSET
0,1
COMMENTS
The median of the probability density function f(x) = 4*x*(Pi/2 - 2*x + x^2/2) for x <= 1, and 4*x*(arcsin(1/x) - arccos(1/x) + 2*sqrt(x^2-1) - (x^2+2)/2) for 1 <= x <= sqrt(2) (Ghosh, 1951).
The second root of 3*x^4 - 16*x^3 + 6*Pi*x^2 - 3 = 0.
LINKS
Birendranath Ghosh, Random distances within a rectangle and between two rectangles, Bulletin of Calcutta Mathematical Society, Vol. 43 (1951), pp. 17-24.
Eric Weisstein's World of Mathematics, Square Line Picking.
EXAMPLE
0.512003269083333882131081199474793545179390944060415...
MATHEMATICA
RealDigits[Root[3*x^4 - 16*x^3 + 6*Pi*x^2 - 3, 2], 10, 120][[1]]
PROG
(PARI) solve(x = 1/2, 1, 3*x^4 - 16*x^3 + 6*Pi*x^2 - 3)
CROSSREFS
Cf. A091505 (mean), A394606 (disk), A394607 (mode).
Sequence in context: A156952 A158748 A351241 * A273874 A086039 A265824
KEYWORD
nonn,cons
AUTHOR
Amiram Eldar, Mar 26 2026
STATUS
approved