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A305324
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Number of one-sided 'divisible' polyominoes of size 2^(n-1), where a 'divisible' polyomino is either a monomino (square) or a polyomino which can be separated into two identical 'divisible' polyominoes.
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0
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OFFSET
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1,3
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COMMENTS
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a(n) is nonzero for any n >= 1. Proof is trivial by induction.
a(n) <= A000988(2^(n-1)) as any polyomino counted here is also counted in A000988.
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LINKS
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EXAMPLE
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For n = 3 (polyominoes of size 4), the 'divisible' polyominoes are the I, O, J, L, S and Z tetrominoes. The T tetromino is not 'divisible'.
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CROSSREFS
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KEYWORD
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nonn,more
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AUTHOR
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EXTENSIONS
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Definition changed and more terms added by John Mason, Sep 20, 2022
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STATUS
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approved
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