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%I #5 Apr 25 2023 07:50:10
%S 1,4,13,37,152,704,5022,42621,420222,5313446,83504848,1668949583,
%T 41600395450,1285489016880,49769130940759
%N Number of ways to place zero or more nonadjacent 0,0 1,0 2,0 2,1 3,0 polyhexes in any orientation on a planar n X n X n triangular grid.
%e Maximal 13 X 13 X 13 example
%e ...............1
%e ..............1.0
%e .............1.1.0
%e ............1.0.0.1
%e ...........0.0.0.0.1
%e ..........0.1.0.0.1.1
%e .........1.0.1.0.0.0.1
%e ........1.0.1.1.0.1.0.0
%e .......1.1.0.0.1.0.1.1.0
%e ......1.0.0.0.0.0.0.1.0.1
%e .....0.0.1.1.1.1.0.0.1.0.1
%e ....0.1.0.0.1.0.0.1.0.0.1.1
%e ...1.1.1.1.0.0.1.1.1.1.0.0.1
%K nonn
%O 3,2
%A _R. H. Hardin_, Jan 22 2009