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A239150 Number of (n+1) X (1+1) 0..3 arrays with no element equal to all horizontal neighbors or unequal to all vertical neighbors, and new values 0..3 introduced in row major order.

%I A239150 #7 Oct 25 2018 09:48:28
%S A239150 1,1,7,17,96,340,1639,6623,29843,126163,554310,2380524,10363965,
%T A239150 44756085,194216303,840357677,3642433780,15771490916,68331367227,
%U A239150 295943443667,1282011757819,5552887116543,24053558944522,104188496250108
%N A239150 Number of (n+1) X (1+1) 0..3 arrays with no element equal to all horizontal neighbors or unequal to all vertical neighbors, and new values 0..3 introduced in row major order.
%H A239150 R. H. Hardin, <a href="/A239150/b239150.txt">Table of n, a(n) for n = 1..210</a>
%F A239150 Empirical: a(n) = 4*a(n-1) + 7*a(n-2) - 26*a(n-3) + 5*a(n-4) + 14*a(n-5).
%F A239150 Empirical g.f.: x*(1 - 3*x - 4*x^2 + 8*x^3) / ((1 - x - x^2)*(1 - 3*x - 9*x^2 + 14*x^3)).
%e A239150 Some solutions for n=5:
%e A239150 ..0..1....0..1....0..1....0..1....0..1....0..1....0..1....0..1....0..1....0..1
%e A239150 ..0..1....0..1....0..1....0..1....0..1....0..1....0..1....0..1....0..1....0..1
%e A239150 ..0..2....1..2....2..0....2..1....2..1....1..0....2..0....2..1....2..0....2..0
%e A239150 ..0..2....1..2....2..0....2..0....2..1....1..0....2..0....2..1....2..0....2..0
%e A239150 ..2..0....1..3....3..0....2..0....1..3....1..0....1..0....3..1....0..1....3..2
%e A239150 ..2..0....1..3....3..0....2..0....1..3....1..0....1..0....3..1....0..1....3..2
%Y A239150 Column 1 of A239155.
%K A239150 nonn
%O A239150 1,3
%A A239150 _R. H. Hardin_, Mar 11 2014