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%I #4 Nov 08 2013 08:24:52
%S 2,5,16,51,180,685,2735,11243,47120,199945,855484,3679681,15882263,
%T 68701955,297607842,1290360591,5597964012,24294536389,105460450143,
%U 457862871585,1988029384006,8632497563339,37485816423762,162782662033991
%N Number of (n+1)X(2+1) 0..3 arrays with no element unequal to a strict majority of its horizontal, vertical and antidiagonal neighbors, with values 0..3 introduced in row major order
%C Column 2 of A231363
%H R. H. Hardin, <a href="/A231357/b231357.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 6*a(n-1) +2*a(n-2) -55*a(n-3) +50*a(n-4) +98*a(n-5) -140*a(n-6) +6*a(n-7) +73*a(n-8) -20*a(n-9) -71*a(n-10) +19*a(n-11) +24*a(n-12) +9*a(n-13) for n>14
%e Some solutions for n=7
%e ..0..0..0....0..0..0....0..0..0....0..0..0....0..0..0....0..0..1....0..0..0
%e ..0..0..0....0..0..1....0..0..0....0..0..0....0..0..0....0..1..1....0..0..1
%e ..0..1..1....0..1..1....0..1..1....0..0..0....1..1..1....1..1..1....0..1..1
%e ..1..1..2....1..1..1....1..1..1....0..0..0....1..1..1....1..1..1....1..1..2
%e ..2..2..2....2..2..2....1..1..2....0..1..1....0..0..0....2..2..2....2..2..2
%e ..2..2..2....2..2..2....1..2..2....1..1..1....0..0..0....2..2..1....2..2..3
%e ..3..3..2....2..2..1....2..2..1....2..2..1....2..2..0....1..1..1....3..3..3
%e ..3..3..2....2..1..1....2..1..1....2..2..1....2..2..0....1..1..1....3..3..3
%K nonn
%O 1,1
%A _R. H. Hardin_, Nov 08 2013