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%I #4 Dec 09 2015 09:00:47
%S 1,2,145,2825,25069,174794,2345091,44474575,628376593,6864539181,
%T 75699824370,1039086421471,15223222698435,201831079064335,
%U 2472305615455965,31106656429366406,419291616977108585
%N Number of nX3 0..n+3-2 arrays with upper left zero and lower right n+3-2 and each element differing from its horizontal and vertical neighbors by one or two.
%C Column 3 of A265447.
%H R. H. Hardin, <a href="/A265442/b265442.txt">Table of n, a(n) for n = 1..210</a>
%e Some solutions for n=4
%e ..0..1..2....0..1..2....0..2..0....0..2..1....0..1..3....0..2..3....0..1..3
%e ..2..3..4....2..3..1....2..0..2....2..3..2....2..3..1....2..3..2....1..0..2
%e ..3..2..3....4..2..3....4..2..4....4..5..4....4..5..3....3..5..3....3..1..3
%e ..2..4..5....5..3..5....5..4..5....5..4..5....5..3..5....2..4..5....1..3..5
%Y Cf. A265447.
%K nonn
%O 1,2
%A _R. H. Hardin_, Dec 09 2015
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