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%I #6 Aug 12 2016 06:53:58
%S 1,5,17,42,155,511,2023,7760,31395,127575,526459,2194344,9206121,
%T 38933281,165380299,706470350,3028761985,13037475319,56289258695,
%U 243772244956,1058354286379,4606025822849,20087808189187,87780004451864
%N Number of 3Xn arrays containing n copies of 0..3-1 with no equal horizontal or antidiagonal neighbors and new values introduced sequentially from 0.
%C Row 3 of A265192.
%H R. H. Hardin, <a href="/A265193/b265193.txt">Table of n, a(n) for n = 1..129</a>
%e Some solutions for n=4
%e ..0..1..2..0....0..1..0..1....0..1..0..2....0..1..2..1....0..1..2..0
%e ..2..0..2..1....0..2..0..2....2..1..0..2....0..1..2..1....2..0..1..2
%e ..1..0..2..1....1..2..1..2....2..1..0..1....2..0..2..0....1..0..1..2
%Y Cf. A265192.
%K nonn
%O 1,2
%A _R. H. Hardin_, Dec 04 2015