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%I #6 Aug 30 2013 10:57:49
%S 1,10,400,57856,31522816,66605547520,554222579875840,
%T 18303191835587117056,2408425353007592768536576,
%U 1265177138001297870205254369280,2655861110791164560222750369099284480
%N Number of different fixed (possibly) disconnected polyominoes (of any area) bounded (not necessarily tightly) by an n*n square.
%F a(n) = 2^(n^2)-2*2^((n-1)*n)+2^((n-1)^2).
%e a(2)=10: the monomino, 4 dominoes (2 strictly disconnected), 4 rotations of the L tromino, and the square tetromino.
%o (PARI) a(n) = 2^(n^2) - 2*2^((n-1)*n) + 2^((n-1)^2); \\ _Michel Marcus_, Aug 30 2013
%Y Cf. A162673, A162674, A162675, A162676.
%K nonn
%O 1,2
%A _David Bevan_, Jul 27 2009
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