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A235456
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Number of non-equivalent (mod D_4) ways to arrange 5 points on an n X n square grid so that no three points are collinear.
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6
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5, 217, 3192, 27041, 149217, 650566, 2317137, 7124316, 19459757, 48617666, 111797647, 241575473
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OFFSET
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3,1
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COMMENTS
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Without the restriction "non-equivalent (mod D_4)" the numbers are given by A194190, n >= 3.
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LINKS
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EXAMPLE
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There are a(3) = 5 non-equivalent ways to place 5 points (X) on a 3 X 3 grid:
X . X X . X . X X X X . X . X
X . X X . . X . X X . . X X .
. 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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