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%I #7 Dec 18 2015 18:17:42
%S 3,11,62,508,6113,111924,3135173,135866492,9010404513,922993092986,
%T 145088171122406,35156227235312406,13079571591787830274,
%U 7493880039061547385152,6595187964080142141837198
%N Number of n X n symmetric 0..2 arrays with no element equal to the product mod 3 of any two of its horizontal and vertical neighbors
%H R. H. Hardin, <a href="/A193499/b193499.txt">Table of n, a(n) for n = 1..19</a>
%e Some solutions for 4X4
%e ..1..0..2..0....2..2..2..0....2..2..0..2....2..2..2..2....0..2..2..0
%e ..0..2..2..2....2..2..0..2....2..2..2..0....2..2..0..2....2..2..0..1
%e ..2..2..0..2....2..0..1..0....0..2..0..1....2..0..1..0....2..0..1..0
%e ..0..2..2..2....0..2..0..2....2..0..1..2....2..2..0..2....0..1..0..1
%K nonn
%O 1,1
%A _R. H. Hardin_ Jul 29 2011
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