%I A155423
%S A155423 1,7,19,52,172,643,2936,14954,84090,537490,4238593,38671134
%N A155423 Number of ways to place zero or more nonadjacent 0,0 1,0 2,1 3,1 4,2 
               5,2 6,3 7,3 polyhexes in any orientation on a planar nXnXn triangular 
               grid.
%e A155423 Maximal 10 X 10 X 10 example
%e A155423 ............0
%e A155423 ...........0.0
%e A155423 ..........1.0.1
%e A155423 .........1.0.0.1
%e A155423 ........0.1.0.1.0
%e A155423 .......0.1.0.0.1.0
%e A155423 ......0.0.1.0.1.0.0
%e A155423 .....0.0.1.0.0.1.0.0
%e A155423 ....0.0.0.1.0.1.0.0.0
%e A155423 ...0.0.0.1.0.0.1.0.0.0
%Y A155423 Sequence in context: A027523 A100545 A100450 this_sequence A155347 A155385 
               A155345
%Y A155423 Adjacent sequences: A155420 A155421 A155422 this_sequence A155424 A155425 
               A155426
%K A155423 nonn
%O A155423 7,2
%A A155423 Ron Hardin (rhhardin(AT)att.net) Jan 22 2009