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Number of planar triangular n X n X n nonnegative integer grids with mirror symmetry about one altitude with every similarly oriented 3 X 3 X 3 subtriangle summing to 6.
0

%I #3 Mar 31 2012 12:35:21

%S 30,67,78,94,85,83,54,55,32,35,32,35,29,38,29,35,32,35,29,38,29,35,32,

%T 35,29,38,29,35,32,35,29,38,29,35,32,35,29,38,29,35,32,35,29,38,29,35,

%U 32,35,29,38,29,35,32,35,29,38,29,35

%N Number of planar triangular n X n X n nonnegative integer grids with mirror symmetry about one altitude with every similarly oriented 3 X 3 X 3 subtriangle summing to 6.

%C Pattern 35 32 35 29 38 29 starts at n=12 and continues through at least n=60.

%e Maximal zeros solution for n=12

%e .............3

%e ............0.0

%e ...........0.3.0

%e ..........3.0.0.3

%e .........0.0.3.0.0

%e ........0.3.0.0.3.0

%e .......3.0.0.3.0.0.3

%e ......0.0.3.0.0.3.0.0

%e .....0.3.0.0.3.0.0.3.0

%e ....3.0.0.3.0.0.3.0.0.3

%e ...0.0.3.0.0.3.0.0.3.0.0

%e ..0.3.0.0.3.0.0.3.0.0.3.0

%K nonn

%O 3,1

%A _R. H. Hardin_ Jan 04 2009