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A143874
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Number of ways of placing kings with no more than 1 mutual attack on an n X n chessboard symmetric under 180 degree rotation.
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1
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1, 2, 3, 7, 18, 111, 497, 4630, 38327, 702227, 10398834
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OFFSET
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0,2
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LINKS
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CROSSREFS
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KEYWORD
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nonn,more,hard
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AUTHOR
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STATUS
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approved
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