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%I #4 Nov 03 2013 16:34:06
%S 0,0,8,48,286,1748,10734,65934,404984,2487534,15279170,93849326,
%T 576451382,3540741892,21748327444,133584927368,820519778376,
%U 5039885260498,30956527928058,190144531428150,1167926290556226
%N Number of 3Xn 0..3 arrays x(i,j) with each element horizontally or antidiagonally next to at least one element with value (x(i,j)+1) mod 4, no adjacent elements equal, and upper left element zero
%C Row 3 of A231108
%H R. H. Hardin, <a href="/A231109/b231109.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 10*a(n-1) -26*a(n-2) +6*a(n-3) +60*a(n-4) -56*a(n-5) -38*a(n-6) +54*a(n-7) -9*a(n-8) +18*a(n-9) -20*a(n-10) +2*a(n-12) for n>16
%e Some solutions for n=4
%e ..0..1..0..1....0..1..2..1....0..1..2..3....0..1..0..3....0..1..2..0
%e ..2..3..2..1....0..3..2..1....0..1..0..1....2..3..2..3....0..3..1..2
%e ..2..3..0..3....2..3..0..3....0..3..2..1....0..1..0..3....2..0..3..2
%K nonn
%O 1,3
%A _R. H. Hardin_, Nov 03 2013
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