The OEIS is supported by the many generous donors to the OEIS Foundation.
Reminder: The OEIS is hiring a new managing editor, and the application deadline is January 26.
Reminder: The OEIS is hiring a new managing editor, and the application deadline is January 26.
%I #3 Mar 31 2012 12:35:23
%S 1,7,19,37,61,257,2034,12328,53385,258324,2321815,29642532,362215522,
%T 3875443645,50070184746,929942357232,22058196563695
%N Number of ways to place zero or more nonadjacent 1,0 2,0 3,1 3,2 3,3 4,1 5,2 polyhexes in any orientation on a planar nXnXn triangular grid.
%C Same series for 1,1 2,1 2,2 3,0 3,1 4,2 4,3 5,3 polyhexes.
%e Maximal 10 X 10 X 10 example
%e ............0
%e ...........0.1
%e ..........0.0.1
%e .........1.1.1.0
%e ........0.0.0.1.0
%e .......0.0.0.1.0.0
%e ......0.1.1.0.0.0.1
%e .....1.1.0.0.1.0.1.0
%e ....1.0.1.0.0.1.1.0.0
%e ...0.0.0.1.0.0.0.1.1.0
%K nonn
%O 5,2
%A _R. H. Hardin_ Jan 22 2009