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A237432
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Number of nonisomorphic Hamiltonian cycles on (4n-2) X (4n-2) square grid of points with four-fold rotational symmetry (and no other symmetry).
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2
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OFFSET
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1,3
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COMMENTS
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For square grids of m X m points, there are solutions only for m = (4n-2).
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LINKS
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FORMULA
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EXAMPLE
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The two cycles counted as a single class for n=2. These are isomorphic (here meaning isomorphic under the full symmetry group of the square), since each is a reflection of the other.
o-o o-o-o-o o-o-o-o o-o
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o o o o-o-o o-o-o o o o
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o o-o o-o-o o-o-o o-o o
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o-o-o o-o o o o-o o-o-o
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o-o-o o o o o o o o-o-o
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o-o-o-o o-o o-o o-o-o-o
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CROSSREFS
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KEYWORD
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nonn,walk,hard,more
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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