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A194609 Half the number of lower triangles of an (n+1) X (n+1) 0..2 array with no element equal to the average of its horizontal and vertical neighbors.

%I A194609 #10 Jun 03 2025 15:50:35
%S A194609 5,96,4322,571364,205801866,202803700252,547917448108462,
%T A194609 4059864930297777162,82468548660331834255159,
%U A194609 4592574521519240269995632810,701184800636550713667143286769980
%N A194609 Half the number of lower triangles of an (n+1) X (n+1) 0..2 array with no element equal to the average of its horizontal and vertical neighbors.
%H A194609 R. H. Hardin, <a href="/A194609/b194609.txt">Table of n, a(n) for n = 1..12</a>
%e A194609 Some solutions for 3X3
%e A194609 ..1......1......0......0......0......2......1......2......0......2......0
%e A194609 ..0.2....2.2....1.2....1.0....2.0....0.1....0.2....1.0....1.0....0.2....2.2
%e A194609 ..2.0.2..0.0.2..2.1.2..2.1.2..2.1.0..1.0.1..0.1.0..2.0.2..0.0.1..1.0.1..2.0.1
%Y A194609 Column 2 of A194615.
%K A194609 nonn
%O A194609 1,1
%A A194609 _R. H. Hardin_, Aug 30 2011