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%I #3 Mar 31 2012 12:35:22
%S 1,7,25,55,184,1073,8931,73812,639377,7143496,110082014,2154472585,
%T 48658986855,1307630014597
%N Number of ways to place zero or more nonadjacent 1,1 2,0 2,1 3,2 4,3 4,4 polyhexes in any orientation on a planar nXnXn triangular grid.
%e Maximal 12 X 12 X 12 example
%e ..............0
%e .............1.0
%e ............0.1.1
%e ...........0.1.0.0
%e ..........1.1.0.0.1
%e .........0.0.0.1.1.0
%e ........0.0.1.0.0.1.0
%e .......1.1.1.0.1.0.1.1
%e ......1.0.0.1.0.1.0.0.0
%e .....0.0.1.0.0.1.0.1.0.0
%e ....1.1.1.0.1.1.0.0.1.1.1
%e ...1.0.0.1.0.0.1.0.1.0.0.1
%K nonn
%O 4,2
%A _R. H. Hardin_ Jan 22 2009