%I #6 Aug 12 2016 06:53:59
%S 1,5,39,357,3471,35003,362265,3821877,40918431,443234475,4847042025,
%T 53425329675,592800026625,6615155585925,74183656771239,
%U 835491101084757,9445356930180735,107140324945955483,1218962144543118009
%N Number of 3Xn arrays containing n copies of 0..3-1 with no element 1 greater than its north neighbor modulo 3 and the upper left element equal to 0.
%C Row 3 of A266455.
%H R. H. Hardin, <a href="/A266456/b266456.txt">Table of n, a(n) for n = 1..93</a>
%e Some solutions for n=4
%e ..0..1..0..1....0..1..1..0....0..0..2..2....0..0..1..0....0..0..1..2
%e ..2..0..0..1....2..1..1..2....2..0..1..1....2..2..1..2....2..0..1..2
%e ..2..2..2..1....2..0..0..2....1..2..1..0....2..1..0..1....1..2..0..1
%Y Cf. A266455.
%K nonn
%O 1,2
%A _R. H. Hardin_, Dec 29 2015