A155397 - OEIS

A155397

Number of ways to place zero or more nonadjacent 0,0 1,0 2,0 3,1 4,0 4,1 5,0 6,0 polyhexes in any orientation on a planar nXnXn triangular grid.

%I #3 Mar 31 2012 12:35:23

%S 1,4,13,45,194,809,3321,15727,81305,509040,3870198,33980590,341474106

%N Number of ways to place zero or more nonadjacent 0,0 1,0 2,0 3,1 4,0 4,1 5,0 6,0 polyhexes in any orientation on a planar nXnXn triangular grid.

%e Maximal 9 X 9 X 9 example

%e ...........1

%e ..........0.1

%e .........1.0.1

%e ........1.0.1.0

%e .......1.0.0.1.1

%e ......0.1.0.0.0.1

%e .....1.1.0.0.0.0.1

%e ....1.0.0.0.1.1.0.0

%e ...1.0.1.1.1.0.1.1.1

%K nonn

%O 6,2

%A _R. H. Hardin_ Jan 22 2009