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%I #3 Mar 31 2012 12:35:23
%S 1,4,10,19,51,170,491,1673,7735,36917,181725,1063340,7115095,51066154,
%T 415590144,3918376915
%N Number of ways to place zero or more nonadjacent 1,1 2,0 2,1 3,2 4,3 5,4 5,5 6,4 polyhexes in any orientation on a planar nXnXn triangular grid.
%e Maximal 10 X 10 X 10 example
%e ............0
%e ...........0.1
%e ..........1.1.0
%e .........0.0.1.0
%e ........1.0.0.1.0
%e .......0.1.1.0.1.1
%e ......0.1.0.0.1.0.0
%e .....0.1.0.1.0.0.0.1
%e ....1.1.0.0.1.1.1.1.0
%e ...0.0.1.0.1.0.0.0.1.0
%K nonn
%O 6,2
%A _R. H. Hardin_ Jan 22 2009