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

%I #3 Mar 31 2012 12:35:22

%S 1,3,7,13,38,180,805,3814,25700,220335,2064779,23174247,331474649,

%T 5713874467,116010028877,2863484145009,86429492811884,

%U 3140385298427338,137283404960168681,7274093873738312075

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

%e Maximal 10 X 10 X 10 example

%e ............0

%e ...........1.0

%e ..........0.1.1

%e .........0.1.0.0

%e ........1.0.0.1.0

%e .......0.1.1.0.1.1

%e ......0.1.0.0.1.0.0

%e .....1.0.0.1.0.0.1.0

%e ....0.1.1.0.1.1.0.1.1

%e ...0.1.0.0.1.0.0.1.0.0

%K nonn

%O 3,2

%A _R. H. Hardin_ Jan 22 2009