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%I #3 Mar 31 2012 12:35:22
%S 1,4,13,28,111,977,7280,55365,714096,13471597,269297226,6772718447,
%T 245090678582,11547321954885,661077498433706,49292298477002834,
%U 4904773608293842400
%N Number of ways to place zero or more nonadjacent 1,0 1,1 2,0 3,1 polyhexes in any orientation on a planar nXnXn triangular grid.
%C Same series for 0,0 1,0 1,1 2,0 2,1 polyhexes.
%e Maximal 9 X 9 X 9 example
%e ...........0
%e ..........1.1
%e .........1.0.1
%e ........0.0.0.0
%e .......0.1.0.1.0
%e ......0.0.1.1.0.0
%e .....1.0.0.0.0.0.1
%e ....0.1.0.1.1.0.1.0
%e ...1.1.0.1.0.1.0.1.1
%K nonn
%O 2,2
%A _R. H. Hardin_ Jan 22 2009