%I #3 Mar 31 2012 12:35:23
%S 1,7,19,52,254,1061,4586,28708,218507,1736540,17357415,205447067,
%T 2686619638
%N Number of ways to place zero or more nonadjacent 0,0 1,0 2,0 2,1 3,0 3,1 4,1 5,1 polyhexes in any orientation on a planar nXnXn triangular grid.
%e Maximal 9 X 9 X 9 example
%e ...........0
%e ..........0.1
%e .........1.1.0
%e ........1.1.0.1
%e .......1.1.0.0.1
%e ......1.0.0.0.1.1
%e .....0.0.0.0.0.1.1
%e ....1.1.1.1.0.0.1.0
%e ...0.0.1.1.1.1.0.1.0
%K nonn
%O 5,2
%A _R. H. Hardin_ Jan 22 2009