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A006763
Number of fixed properly-3-dimensional polyominoes with n cells.
(Formerly M5232)
2
0, 0, 0, 32, 348, 2836, 21225, 154741, 1123143, 8185403, 60088748, 444688325, 3317057654, 24925158492, 188543716451, 1434760675947, 10976610064899, 84379534826376, 651441493579872
OFFSET
1,4
REFERENCES
N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
LINKS
W. F. Lunnon, Counting multidimensional polyominoes. Computer Journal 18 (1975), no. 4, pp. 366-367.
FORMULA
a(n) = A001931(n) - 3 * (A001168(n) - 1) for n > 1. - Sean A. Irvine, Jul 27 2017
MATHEMATICA
A001931 = Cases[Import["https://oeis.org/A001931/b001931.txt", "Table"], {_, _}][[All, 2]];
A001168 = Cases[Import["https://oeis.org/A001168/b001168.txt", "Table"], {_, _}][[All, 2]];
a[n_] := If[n == 1, 0, A001931[[n]] - 3 (A001168[[n]] - 1)];
a /@ Range[1, 19] (* Jean-François Alcover, Sep 22 2019 *)
CROSSREFS
A column of A195739.
Sequence in context: A240293 A254953 A335612 * A158074 A200531 A302320
KEYWORD
nonn,more
EXTENSIONS
More terms from Jean-François Alcover, Sep 22 2019
STATUS
approved