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A112580 Number of 3-D arrays of nonnegative integers with plane sums 2. 2
1, 12, 1152, 431424, 427723200, 920031955200, 3777894212198400, 27039993414897254400, 315084437077115278540800, 5667616936309704095784960000, 150796432741520745587273564160000 (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 with first term 1).

EXAMPLE

a(2)=12: eight 0-1 arrays and four with 2s at opposite vertices.

CROSSREFS

Cf. A001499 (2-D case), A112578, A112579.

Sequence in context: A112457 A091782 A291952 * A229691 A180586 A178529

Adjacent sequences:  A112577 A112578 A112579 * A112581 A112582 A112583

KEYWORD

nonn,easy

AUTHOR

Peter J. Cameron, Sep 14 2005

STATUS

approved

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Last modified May 16 06:43 EDT 2022. Contains 353693 sequences. (Running on oeis4.)