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A235458
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Number of non-equivalent (mod D_4) ways to arrange 7 points on an n X n square grid so that no three points are collinear.
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6
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28, 3385, 134353, 1958674, 19929645, 138586349, 753795278, 3356614240, 13108210508, 44374441652, 137349454120
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OFFSET
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4,1
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COMMENTS
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Without the restriction "non-equivalent (mod D_4)" the numbers are given by A194192, n >= 4.
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LINKS
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EXAMPLE
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There are a(4) = 28 non-equivalent ways to place 7 points (X) on a 4 X 4 grid. Example:
. X X .
. . . X
X . . X
X X . .
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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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STATUS
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approved
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