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%I #3 Mar 31 2012 12:35:35
%S 1,8,3,8,99,364,2718,70603,526484,11908924,931368996,15702838676,
%T 958018305487,191827791698093
%N Number of nXnXn triangular nonnegative integer arrays, symmetric under 120 degree rotation, with all sums of an element and its neighbors <= 7
%e Some solutions for n=4
%e .....2........0........3........4........0........2........3........0...
%e ....0.2......1.0......0.0......1.0......1.1......1.1......0.1......0.1..
%e ...2.1.0....0.1.1....0.1.0....0.0.1....1.0.1....1.0.1....1.1.0....1.4.0.
%e ..2.0.2.2..0.1.0.0..3.0.0.3..4.1.0.4..0.1.1.0..2.1.1.2..3.0.1.3..0.0.1.0
%e ------
%e .....0........1........2........1........2........4........7........0...
%e ....1.0......1.0......0.1......0.0......1.0......1.0......0.0......1.1..
%e ...0.3.1....0.2.1....1.1.0....0.5.0....0.1.1....0.1.1....0.0.0....1.1.1.
%e ..0.1.0.0..1.1.0.1..2.0.1.2..1.0.0.1..2.1.0.2..4.1.0.4..7.0.0.7..0.1.1.0
%K nonn
%O 0,2
%A _R. H. Hardin_ Oct 09 2009