%I #6 Dec 18 2015 18:18:47

%S 1,11,1202,750092,2555361596,47506658438246,4819736584585663322,

%T 2668450108003354942469312,8062352020337952090889367491226,

%U 132932519318468579668067283705239149526

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

%C Diagonal of A233018

%H R. H. Hardin, <a href="/A233012/b233012.txt">Table of n, a(n) for n = 1..12</a>

%e Some solutions for n=3

%e ..0..1..0....0..0..0....0..0..0....0..0..0....0..1..0....0..0..0....0..1..3

%e ..1..3..1....0..0..0....0..0..0....0..1..1....0..1..1....0..0..1....0..1..1

%e ..0..1..0....0..0..1....0..1..1....1..1..1....2..3..3....0..0..0....1..1..0

%K nonn

%O 1,2

%A _R. H. Hardin_, Dec 03 2013