%I #8 Dec 10 2015 01:56:09
%S 81,780,4560,48816,516912,10584000,408445632,17222950080,
%T 1397673066240,214644729219840,36193471662355200,11735368648637414400,
%U 7204350072147674803200,4859051673972177459072000
%N Number of (n+1) X (n+1) 0..2 arrays with every 2 X 3 or 3 X 2 subblock having exactly two counterclockwise and two clockwise edge increases.
%C Diagonal of A206094.
%H R. H. Hardin, <a href="/A206086/b206086.txt">Table of n, a(n) for n = 1..20</a>
%e Some solutions for n=4:
%e ..1..0..2..1..1....2..0..1..0..0....1..2..2..1..0....2..0..2..2..0
%e ..1..0..0..2..1....2..0..0..2..0....0..1..2..2..1....2..2..0..2..2
%e ..0..2..0..0..2....0..2..0..0..1....0..0..1..2..2....1..2..2..0..2
%e ..0..0..2..0..0....0..0..1..0..0....2..0..0..1..2....0..1..2..2..0
%e ..1..0..0..2..2....1..0..0..1..1....0..1..0..0..1....0..0..1..2..2
%K nonn
%O 1,1
%A _R. H. Hardin_, Feb 03 2012