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Number of one-sided strictly 3-dimensional polyominoes with n cells.
(Formerly M3038)
2

%I M3038 #29 Dec 26 2023 06:38:38

%S 0,0,0,3,17,131,915,6553,47026,341888,2505449,18534827,138224058,

%T 1038594326,7856087894,59782042225,457359506070,3515816578512,

%U 27143401299351,210372490707568

%N Number of one-sided strictly 3-dimensional polyominoes with n cells.

%D N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

%H W. F. Lunnon, <a href="http://dx.doi.org/10.1093/comjnl/18.4.366">Counting multidimensional polyominoes</a>, Computer Journal 18 (4) (1975) 366-367.

%t A[s_Integer] := With[{s6 = StringPadLeft[ToString[s], 6, "0"]}, Cases[ Import["https://oeis.org/A" <> s6 <> "/b" <> s6 <> ".txt", "Table"], {_, _}][[All, 2]]];

%t A000105 = A@000105;

%t A000162 = A@000162;

%t a[n_] := A000162[[n]] - A000105[[n + 1]];

%t a /@ Range[16] (* _Jean-François Alcover_, Jan 16 2020 *)

%Y A column of A195738.

%K nonn,more

%O 1,4

%A _N. J. A. Sloane_

%E a(11) corrected and a(13)-a(16) from A000162-A000105 by _Jean-François Alcover_, Jan 16 2020

%E Name clarified and a(17)-a(20) from A000162-A000105 by _John Mason_, Dec 26 2023