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%I #6 Dec 18 2015 18:18:47
%S 3,18,246,5808,316800,33994188,8119777890,3947661560964,
%T 4209693243140760,9272914213858594488,44451105435218301006576,
%U 443715189648501201190713852,9592990624095118315413686008902,434027944128749167232792242832245920
%N Number of n X n 0..2 arrays with no element x(i,j) adjacent to value 2-x(i,j) horizontally, diagonally or antidiagonally
%C Diagonal of A232920
%H R. H. Hardin, <a href="/A232916/b232916.txt">Table of n, a(n) for n = 1..16</a>
%e Some solutions for n=4
%e ..2..2..2..2....1..0..1..2....2..2..2..2....2..2..2..1....2..2..2..2
%e ..2..2..1..2....1..0..1..2....2..1..2..1....2..2..2..2....2..1..2..1
%e ..1..2..1..2....1..0..1..2....2..2..2..1....1..2..1..2....2..1..2..2
%e ..1..2..2..2....1..2..1..0....1..2..2..1....1..0..1..2....2..1..2..2
%K nonn
%O 1,1
%A _R. H. Hardin_, Dec 02 2013
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