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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 5 X 5 X 5 subtriangle summing to 5.
0

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

%S 144,321,322,328,186,123,89,49,37,31,27,27,27,27,27,27,27,27,27,27,27,

%T 27,27,27,27,27,27,27,27,27,27,27,27,27,27,27,27,27,27,27,27,27,27,27,

%U 27,27,27,27,27,27,27,27,27,27,27,27

%N Number of planar triangular n X n X n nonnegative integer grids with mirror symmetry about one altitude with every similarly oriented 5 X 5 X 5 subtriangle summing to 5.

%C Value 27 starts at n=15 and continues through at least n=60.

%e Maximal zeros solution for n=15

%e ................2

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

%e ..............0.2.0

%e .............0.0.0.0

%e ............0.0.1.0.0

%e ...........0.0.1.1.0.0

%e ..........2.0.0.0.0.0.2

%e .........0.0.0.1.1.0.0.0

%e ........0.2.0.0.0.0.0.2.0

%e .......0.0.0.0.1.1.0.0.0.0

%e ......0.0.1.0.0.1.0.0.1.0.0

%e .....0.0.1.1.0.0.0.0.1.1.0.0

%e ....2.0.0.0.0.0.2.0.0.0.0.0.2

%e ...0.0.0.1.1.0.0.0.0.1.1.0.0.0

%e ..0.2.0.0.0.0.0.2.0.0.0.0.0.2.0

%K nonn

%O 5,1

%A _R. H. Hardin_ Jan 04 2009