A155428 - OEIS

A155428

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.

%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