%I #9 Mar 15 2023 16:27:11
%S 5,67,4192,587208,147512732,58668937932,34119101220224,
%T 27451586022436696,29334574202437277520,40343697156563884675488,
%U 69646199705725564208484736,147875840329637502384856552096,379682313150983568999164195148800
%N Number of n X 3 nonnegative integer arrays with new values 0 upwards introduced in row major order and no element equal to any diagonal or antidiagonal neighbor (colorings ignoring permutations of colors).
%H Andrew Howroyd, <a href="/A207979/b207979.txt">Table of n, a(n) for n = 1..190</a> (terms 1..16 from R. H. Hardin)
%e Some solutions for n=4
%e ..0..0..0....0..0..0....0..0..1....0..0..0....0..0..0....0..0..0....0..1..0
%e ..1..1..1....1..1..1....1..2..1....1..1..2....1..1..1....1..2..1....2..1..0
%e ..0..2..2....2..0..2....1..2..0....2..0..0....0..2..0....0..0..0....0..1..3
%e ..1..1..0....1..0..1....0..2..0....3..1..4....1..1..0....2..1..1....0..4..0
%Y Column 3 of A207981.
%K nonn
%O 1,1
%A _R. H. Hardin_, Feb 22 2012
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