Reminder: The OEIS is hiring a new managing editor, and the application deadline is January 26.
%I #3 Mar 31 2012 12:35:22
%S 1,4,10,45,176,869,5649,44314,456024,5472215,82109824,1515983373,
%T 34737855825,992142189277
%N Number of ways to place zero or more nonadjacent 0,0 1,0 2,0 3,0 polyhexes in any orientation on a planar nXnXn triangular grid.
%e Maximal 12 X 12 X 12 example
%e ..............0
%e .............1.0
%e ............1.0.0
%e ...........1.0.0.1
%e ..........1.0.1.0.1
%e .........0.0.0.1.0.1
%e ........1.0.1.0.1.0.1
%e .......1.0.1.0.0.1.0.0
%e ......1.0.1.0.0.0.0.0.1
%e .....1.0.1.0.1.1.1.1.0.1
%e ....0.0.0.0.0.0.0.0.0.0.1
%e ...0.1.1.1.1.0.1.1.1.1.0.1
%K nonn
%O 3,2
%A _R. H. Hardin_ Jan 22 2009