A155323 - OEIS

A155323

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

%I #3 Mar 31 2012 12:35:22

%S 1,7,19,37,61,547,3879,20553,82301,862099,11383399,147116137,

%T 1584915709,26192809787,600459150255,15941874201057

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

%C Same series for 0,0 1,0 2,0 2,1 2,2 3,2 4,2 polyhexes.

%e Maximal 9 X 9 X 9 example

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

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

%e .........1.1.1

%e ........0.0.1.0

%e .......0.0.1.0.0

%e ......0.0.0.0.0.0

%e .....1.0.1.0.1.1.1

%e ....0.1.1.0.1.1.0.0

%e ...1.1.1.0.1.0.1.0.0

%K nonn

%O 4,2

%A _R. H. Hardin_ Jan 22 2009