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A234354
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Number of non-equivalent (mod D_3) ways to arrange 6 indistinguishable points on a triangular grid of side n so that no three points are collinear.
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4
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1, 47, 1112, 11743, 82988, 433372, 1820163, 6459496, 20287372, 57129426, 147915285, 356109110, 804785159, 1722171831
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OFFSET
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4,2
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COMMENTS
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Without the restriction "non-equivalent (mod D_3)" the numbers are given by A194134.
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LINKS
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EXAMPLE
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There is a(4) = 1 non-equivalent way to arrange 6 indistinguishable points (x) on a triangular grid of side 4:
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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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