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A248598 a(n) = (2*n+23)*n*(n-1), a coefficient appearing in the formula a(n)*Pi/324+n+1 giving the average number of regions into which n random planes divide the cube. 0
0, 0, 54, 174, 372, 660, 1050, 1554, 2184, 2952, 3870, 4950, 6204, 7644, 9282, 11130, 13200, 15504, 18054, 20862, 23940, 27300, 30954, 34914, 39192, 43800, 48750, 54054, 59724, 65772, 72210, 79050, 86304, 93984, 102102, 110670, 119700 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

COMMENTS

The analog formula giving the average number of regions into which n random lines divide the square is n*(n-1)*Pi/16+n+1.

REFERENCES

Steven R. Finch, Mathematical Constants, Cambridge University Press, 2003, Section 8.1 Geometric probability constants, p. 482.

LINKS

Table of n, a(n) for n=0..36.

Eric Weisstein's MathWorld, Square Division by Lines

Eric Weisstein's MathWorld, Cube Division by Planes

Index entries for linear recurrences with constant coefficients, signature (4,-6,4,-1).

FORMULA

a(n) = 4*a(n-1)-6*a(n-2)+4*a(n-3)-a(n-4). - Colin Barker, Oct 09 2014

G.f.: -6*x^2*(7*x-9) / (x-1)^4. - Colin Barker, Oct 09 2014

MATHEMATICA

a[n_] := (2*n+23)*n*(n-1); Table[a[n], {n, 0, 40}]

PROG

(PARI) concat([0, 0], Vec(-6*x^2*(7*x-9)/(x-1)^4 + O(x^100))) \\ Colin Barker, Oct 09 2014

CROSSREFS

Sequence in context: A044767 A250792 A044980 * A157428 A068380 A187299

Adjacent sequences:  A248595 A248596 A248597 * A248599 A248600 A248601

KEYWORD

nonn,easy

AUTHOR

Jean-Fran├žois Alcover, Oct 09 2014

STATUS

approved

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Last modified December 16 00:33 EST 2019. Contains 330013 sequences. (Running on oeis4.)