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%I #6 Aug 12 2016 06:54:00
%S 2,2,2,2,2,5,14,44,127,325,779,1794,3988,8830,19835,45596,108019,
%T 262831,649761,1616713,4017231,9918784,24298996,59106476,143053467,
%U 345488183,834978807,2023884377,4926308772,12044390597,29559301172,72735281709
%N Number of 3Xn arrays containing n copies of 0..3-1 with no element 1 greater than its west, northeast or northwest neighbor modulo 3 and the upper left element equal to 0.
%C Row 3 of A266994.
%H R. H. Hardin, <a href="/A266995/b266995.txt">Table of n, a(n) for n = 1..106</a>
%e Some solutions for n=7
%e ..0..2..1..0..2..1..0....0..0..0..0..2..2..1....0..0..0..2..2..1..1
%e ..1..0..2..1..0..2..1....0..0..2..2..2..1..1....0..2..2..2..1..1..0
%e ..2..1..0..2..1..0..2....0..2..2..1..1..1..1....2..2..1..1..1..0..0
%Y Cf. A266994.
%K nonn
%O 1,1
%A _R. H. Hardin_, Jan 08 2016