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A112579 Number of 3-D arrays of 0's and 1's with plane sums 2. 2
0, 8, 900, 366336, 378028800, 833156928000, 3477528928742400, 25183876050321408000, 296058177312000019660800, 5362158372805111867637760000, 143458227395428379364635443200000 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

REFERENCES

P. J. Cameron and T. W. Mueller, Decomposable functors and the exponential principle, II, in preparation

LINKS

Table of n, a(n) for n=1..11.

P. J. Cameron and T. W. Mueller, Decomposable functors and the exponential principle, II, arXiv:0911.3760 [math.CO]

FORMULA

a(n) = b(n) + Sum (k/n)*(n choose k)^3*b(k)*a(n-k), where b(n) counts indecomposable arrays (A112578).

EXAMPLE

a(2)=8: six pairs of opposite edges and two inscribed tetrahedra.

CROSSREFS

Cf. A001499 (2-D case), A112578, A112580.

Sequence in context: A265239 A290023 A112578 * A064072 A146536 A189646

Adjacent sequences:  A112576 A112577 A112578 * A112580 A112581 A112582

KEYWORD

nonn,easy

AUTHOR

Peter J. Cameron, Sep 14 2005

STATUS

approved

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Last modified June 30 03:34 EDT 2022. Contains 354913 sequences. (Running on oeis4.)