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%I #3 Mar 31 2012 12:35:22
%S 1,13,37,73,333,3889,39159,271617,3012146,61623325,1541710905,
%T 35611299121,1059291769629,47181801621713,2749984961944969
%N Number of ways to place zero or more nonadjacent 1,0 2,0 2,1 2,2 3,1 4,1 polyhexes in any orientation on a planar nXnXn triangular grid.
%e Maximal 12 X 12 X 12 example
%e ..............0
%e .............0.1
%e ............1.1.1
%e ...........0.0.1.0
%e ..........0.0.0.1.0
%e .........0.1.0.0.0.1
%e ........1.1.1.0.1.1.0
%e .......0.0.1.0.1.1.0.0
%e ......0.1.0.1.0.0.1.0.0
%e .....1.1.0.0.0.1.0.0.0.1
%e ....1.1.0.1.1.1.0.1.1.1.0
%e ...0.0.1.0.0.1.1.0.0.1.1.0
%K nonn
%O 4,2
%A _R. H. Hardin_ Jan 22 2009