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A047944
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Number of 9-colorings of an n X n grid, up to rotational symmetry.
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3
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1, 9, 1665, 96870249, 463255057977921, 179474496923598616041129, 5632099886234793640483695986653185, 14316042242555870306568544190208626253583093449, 2947546144434645792880218215353988087374626027116634833972481
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OFFSET
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0,2
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LINKS
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FORMULA
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a(n) = (m^(n^2) + 2 m^((n^2 + 3 (n mod 2))/4) + m^((n^2 + (n mod 2))/2))/4, with m = 9.
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CROSSREFS
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KEYWORD
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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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