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A056846 Number of polyominoids containing n squares: these are 2-dimensional polyominoes in a three-dimensional grid (edge-connected squares, like the floors, ceilings and walls of a building). 2
1, 2, 11, 80, 780, 8781, 104828, 1298506, 16462696, 212457221, 2780615627, 36817036777 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

REFERENCES

R. A. Epstein, The Theory of Gambling and Statistical Logic, 1977, Academic Press, ISBN 0-12-240760-1 (pages 362-369 discuss polyforms, including Epstein's polyominoids).

LINKS

Table of n, a(n) for n=1..12.

M. Keller, Counting polyforms

CROSSREFS

Sequence in context: A027110 A118969 A181068 * A277500 A197718 A215654

Adjacent sequences:  A056843 A056844 A056845 * A056847 A056848 A056849

KEYWORD

nonn,nice

AUTHOR

N. J. A. Sloane, James A. Sellers, Aug 28 2000

EXTENSIONS

Corrected and extended by Joseph Myers, Sep 24 2002

STATUS

approved

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Last modified December 18 23:46 EST 2018. Contains 318245 sequences. (Running on oeis4.)