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A233084 Number of 3 X n 0..3 arrays with no element x(i,j) adjacent to value 3-x(i,j) horizontally or antidiagonally, top left element zero, and 1 appearing before 2 in row major order.

%I A233084 #8 Oct 07 2018 08:36:22
%S A233084 10,122,1985,32414,529862,8662343,141615905,2315203034,37850025182,
%T A233084 618789971363,10116268804625,165385509256454,2703799908891302,
%U A233084 44202989610119183,722651215442080145,11814241158484224674
%N A233084 Number of 3 X n 0..3 arrays with no element x(i,j) adjacent to value 3-x(i,j) horizontally or antidiagonally, top left element zero, and 1 appearing before 2 in row major order.
%H A233084 R. H. Hardin, <a href="/A233084/b233084.txt">Table of n, a(n) for n = 1..210</a>
%F A233084 Empirical: a(n) = 19*a(n-1) - 45*a(n-2) + 27*a(n-3) for n>5.
%F A233084 Empirical g.f.: x*(10 - 68*x + 117*x^2 - 81*x^3 + 27*x^4) / ((1 - x)*(1 - 18*x + 27*x^2)). - _Colin Barker_, Oct 07 2018
%e A233084 Some solutions for n=4:
%e A233084 ..0..1..0..2....0..1..1..3....0..1..3..1....0..1..3..2....0..1..0..2
%e A233084 ..1..0..0..0....1..1..3..3....0..1..3..3....1..3..2..3....0..0..0..0
%e A233084 ..1..0..0..2....1..3..3..2....3..3..1..1....3..3..3..2....1..0..1..0
%Y A233084 Row 3 of A233082.
%K A233084 nonn
%O A233084 1,1
%A A233084 _R. H. Hardin_, Dec 03 2013