The On-Line Encyclopedia of Integer Sequences (OEIS)

A234354 revision #7

A234354

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.

1, 47, 1112, 11743, 82988, 433372, 1820163, 6459496, 20287372, 57129426, 147915285, 356109110, 804785159, 1722171831

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OFFSET

4,2

COMMENTS

Column 6 of triangle A234350.

Without the restriction "non-equivalent (mod D_3)" the numbers are given by A194134.

LINKS

EXAMPLE

There is a(4) = 1 non-equivalent way to arrange 6 indistinguishable points (x) on a triangular grid of side 4:

x x

x . x

. x x .

CROSSREFS

Arranging 3 points: A234351

Arranging 4 points: A234352

Arranging 5 points: A234353

KEYWORD

nonn,more

AUTHOR

EXTENSIONS

a(14)-a(17) from Heinrich Ludwig, April 19, 2016

STATUS

editing