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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 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.)