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A162677 Number of different fixed (possibly) disconnected polyominoes (of any area) bounded (not necessarily tightly) by an n*n square. 5
1, 10, 400, 57856, 31522816, 66605547520, 554222579875840, 18303191835587117056, 2408425353007592768536576, 1265177138001297870205254369280, 2655861110791164560222750369099284480 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..11.

FORMULA

a(n) = 2^(n^2)-2*2^((n-1)*n)+2^((n-1)^2).

EXAMPLE

a(2)=10: the monomino, 4 dominoes (2 strictly disconnected), 4 rotations of the L tromino, and the square tetromino.

PROG

(PARI) a(n) = 2^(n^2) - 2*2^((n-1)*n) + 2^((n-1)^2); \\ Michel Marcus, Aug 30 2013

CROSSREFS

Cf. A162673, A162674, A162675, A162676.

Sequence in context: A183487 A172505 A098722 * A041767 A130557 A231052

Adjacent sequences:  A162674 A162675 A162676 * A162678 A162679 A162680

KEYWORD

nonn

AUTHOR

David Bevan, Jul 27 2009

STATUS

approved

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Last modified July 5 17:29 EDT 2020. Contains 335473 sequences. (Running on oeis4.)