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%I #3 Mar 31 2012 12:35:23
%S 1,4,10,19,31,142,704,3110,11340,67080,521405,4456035,36267075,
%T 359062706,4494388097,66854020627,1071365619565,19550448735686
%N Number of ways to place zero or more nonadjacent 0,0 1,0 1,1 2,0 2,2 3,1 3,2 4,2 polyhexes in any orientation on a planar nXnXn triangular grid.
%e Maximal 9 X 9 X 9 example
%e ...........1
%e ..........1.1
%e .........1.0.1
%e ........0.1.1.0
%e .......0.0.1.0.0
%e ......0.0.0.0.0.0
%e .....1.1.1.0.1.1.1
%e ....1.0.1.0.0.1.0.1
%e ...1.1.1.0.0.0.1.1.1
%K nonn
%O 4,2
%A _R. H. Hardin_ Jan 22 2009