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Number of 4Xn 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
1

%I #4 Dec 03 2013 21:25:21

%S 36,1094,41675,1588262,60632429,2315298290,88417171553,3376534087742,

%T 128945571641429,4924269835697930,188051703434648393,

%U 7181459293743807062,274250946368131595069,10473300553139406347810,399962246005236076609073

%N Number of 4Xn 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 Row 4 of A233082

%H R. H. Hardin, <a href="/A233085/b233085.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 49*a(n-1) -450*a(n-2) +1466*a(n-3) -1853*a(n-4) +789*a(n-5) for n>8

%e Some solutions for n=3

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

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

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

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

%K nonn

%O 1,1

%A _R. H. Hardin_, Dec 03 2013