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%I #8 Mar 26 2023 10:21:57
%S 0,2,8,42,576,5492,68958,814418,9982880,122186774,1509756240,
%T 18739734568,233756282022,2928054874344,36812296612552,
%U 464358008157458,5874864170778700,74526122250575078,947703833383753558
%N Number of 3 X n arrays containing n copies of 0..3-1 with every element equal to at least one horizontal or antidiagonal neighbor and the top left element equal to 0.
%C Row 3 of A267617.
%H R. H. Hardin, <a href="/A267619/b267619.txt">Table of n, a(n) for n = 1..43</a>
%e Some solutions for n=4
%e ..0..0..2..0....0..0..2..2....0..0..1..1....0..0..2..2....0..0..0..0
%e ..2..2..0..1....1..1..0..0....0..0..2..2....1..1..0..0....2..2..1..1
%e ..2..1..1..1....1..1..2..2....1..1..2..2....2..2..1..1....2..2..1..1
%Y Cf. A267617.
%K nonn
%O 1,2
%A _R. H. Hardin_, Jan 18 2016
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