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%I #7 Dec 09 2017 19:46:05
%S 0,0,0,0,9,1875,52323,695616,5840088,35715529,172520643,708871152,
%T 2517687856,8023634766,23292994812,62357664744,155765126265,
%U 367482996726,822866800569,1762214894004,3621792301059
%N Number of ways to arrange 7 indistinguishable points on an n X n X n triangular grid so that no three points are collinear at any angle.
%C Column 7 of A194136.
%e Some solutions for 5 X 5 X 5:
%e ......0..........0..........0..........0..........0..........0..........0
%e .....0.1........1.0........1.0........0.1........0.1........1.0........1.1
%e ....1.0.1......1.0.1......0.1.1......1.1.0......1.1.0......0.1.1......0.0.1
%e ...1.0.1.0....0.1.0.1....1.0.0.1....1.0.0.1....0.0.1.1....1.1.0.0....1.1.0.0
%e ..0.1.0.1.0..0.1.0.1.0..0.1.1.0.0..0.0.1.1.0..1.0.1.0.0..0.0.1.0.1..0.0.1.1.0
%K nonn
%O 1,5
%A _R. H. Hardin_, Aug 17 2011
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