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%I #3 Mar 31 2012 12:35:23
%S 1,7,19,37,61,248,1219,8302,40919,212586,1454728,13983083,157730943,
%T 1851906541,23225168793,351573878630,6540083828707
%N Number of ways to place zero or more nonadjacent 2,0 3,1 3,2 4,2 4,3 4,4 5,2 6,2 polyhexes in any orientation on a planar nXnXn triangular grid.
%e Maximal 11 X 11 X 11 example
%e .............0
%e ............0.0
%e ...........0.0.1
%e ..........0.1.1.0
%e .........1.1.1.0.0
%e ........0.0.0.1.0.0
%e .......0.0.1.0.1.0.1
%e ......0.1.1.0.0.0.1.0
%e .....1.1.1.0.1.1.1.0.0
%e ....0.0.0.1.0.0.1.1.0.0
%e ...0.0.0.0.1.0.0.0.1.0.0
%K nonn
%O 6,2
%A _R. H. Hardin_ Jan 22 2009