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A130622
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Number of polyominoes with perimeter at most 2n.
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0
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0, 1, 2, 5, 11, 36, 122, 538, 2526, 13166, 71153, 400109, 2300430, 13504780, 80547558, 487327904
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OFFSET
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1,3
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COMMENTS
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The perimeter of a polyomino is always even.
Is there another prime term beyond {2, 5, 11}?
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LINKS
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CROSSREFS
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Cf. A131482 (number of n-celled polyominoes with perimeter 2n+2).
Cf. A130866 (number of polyominoes with at most n cells).
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KEYWORD
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hard,more,nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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