A233076 - OEIS

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

%S 1,14,1985,1588262,6938214854,165407945648306,21520525142517911969,

%T 15280137439726087042287674,59207172638901578439239726940974,

%U 1251961921151721201415260511387809535370

%N Number of n 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

%C Diagonal of A233082

%H R. H. Hardin, <a href="/A233076/b233076.txt">Table of n, a(n) for n = 1..13</a>

%e Some solutions for n=3

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

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

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

%K nonn

%O 1,2

%A _R. H. Hardin_, Dec 03 2013