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A171860 Number of n-cell fixed polycubes that are proper in n-2 dimensions. 3
0, 1, 17, 348, 8640, 254800, 8749056, 343901376, 15257600000, 755110160640, 41278242816000, 2471677136321536, 160961785787056128, 11330322120000000000, 857485369051342438400, 69444841895469240729600, 5993559601317659925282816, 549242871950650346384195584 (list; graph; refs; listen; history; text; internal format)
OFFSET

2,3

REFERENCES

Gill Barequet, Solomon W. Golomb, and David A. Klarner, Polyominoes. (This is a revision, by G. Barequet, of the chapter of the same title originally written by the late D. A. Klarner for the first edition, and revised by the late S. W. Golomb for the second edition.) Preprint, 2016, http://www.csun.edu/~ctoth/Handbook/chap14.pdf

G. Barequet, M. Shalah, Automatic Proofs for Formulae Enumerating Proper Polycubes, 31st International Symposium on Computational Geometry (SoCG'15).  Editors: Lars Arge and J├ínos Pach; pp. 19-22, 2015.

R. Barequet, G. Barequet, and G. Rote, Formulae and growth rates of high-dimensional polycubes, Combinatorica, 30 (2010), 257-275. See Th. 6.

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 2..100

A. Asinowski, G. Barequet, R. Barequet, G. Rote, Proper n-Cell Polycubes in n-3 Dimensions, J. Int. Seq. 15 (2012) #12.8.4.

FORMULA

a(n) = 2^(n-3)*n^(n-5)*(n-2)*(2*n^2 - 6*n + 9).

PROG

(MAGMA) [2^(n-3)*n^(n-5)*(n-2)*(2*n^2-6*n+9): n in [2..20]]; // Vincenzo Librandi, May 26 2011

CROSSREFS

Cf. A127670, A191092.

Sequence in context: A012112 A294435 A137246 * A191589 A194729 A081421

Adjacent sequences:  A171857 A171858 A171859 * A171861 A171862 A171863

KEYWORD

nonn

AUTHOR

N. J. A. Sloane, Oct 16 2010

EXTENSIONS

Slightly edited by Gill Barequet, May 25 2011

STATUS

approved

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Last modified November 21 03:01 EST 2018. Contains 317427 sequences. (Running on oeis4.)