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%I #3 Mar 31 2012 12:35:35
%S 1,6,2,5,39,122,604,8064,40848,495985,16474555,153952919,4118194905,
%T 283350411160,6779925069586,398461742491565,59492448257857640
%N Number of nXnXn triangular nonnegative integer arrays, symmetric under 120 degree rotation, with all sums of an element and its neighbors <= 5
%e Some solutions for n=4
%e .....1........1........2........0........0........1........0........2...
%e ....1.0......0.1......0.0......1.0......0.0......0.0......0.0......1.0..
%e ...0.1.1....1.1.0....0.0.0....0.0.1....0.3.0....0.1.0....0.0.0....0.1.1.
%e ..1.1.0.1..1.0.1.1..2.0.0.2..0.1.0.0..0.0.0.0..1.0.0.1..0.0.0.0..2.1.0.2
%e ------
%e .....2........0........3........0........0........2........2........1...
%e ....0.0......0.1......0.0......0.0......0.0......0.1......0.0......1.0..
%e ...0.2.0....1.2.0....0.0.0....0.1.0....0.5.0....1.0.0....0.3.0....0.0.1.
%e ..2.0.0.2..0.0.1.0..3.0.0.3..0.0.0.0..0.0.0.0..2.0.1.2..2.0.0.2..1.1.0.1
%K nonn
%O 0,2
%A _R. H. Hardin_ Oct 09 2009
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