A155305 - OEIS

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A155305

Number of ways to place zero or more nonadjacent 1,1 2,0 2,1 3,2 3,3 4,4 polyhexes in any orientation on a planar nXnXn triangular grid.

1, 7, 25, 64, 217, 1298, 10738, 90390, 827265, 9950319, 159818687, 3209355205, 75527888278, 2156343784054

(list; graph; refs; listen; history; text; internal format)

OFFSET

4,2

LINKS

Table of n, a(n) for n=4..17.

EXAMPLE

Maximal 11 X 11 X 11 example

.............1

............0.1

...........0.1.0

..........0.0.1.1

.........0.0.1.0.0

........1.0.0.0.0.1

.......0.1.1.0.1.1.0

......1.1.0.0.0.0.1.1

.....1.0.0.1.0.1.0.0.1

....0.0.1.1.0.0.1.1.0.0

...0.1.1.0.1.0.1.0.1.1.0

CROSSREFS

Sequence in context: A299273 A001845 A127765 * A155290 A056685 A299262

Adjacent sequences: A155302 A155303 A155304 * A155306 A155307 A155308

KEYWORD

nonn

AUTHOR

R. H. Hardin Jan 22 2009

STATUS

approved