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%I #4 Dec 09 2015 10:44:40
%S 1,26,550,9808,290140,8526762,226627855,6429210362,189020997503,
%T 5485167198242,160226445169831,4738482482000394,140498396836803614,
%U 4175334634703864434,124606393191706378406,3729279022290970831400
%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 antidiagonal neighbors by one or two.
%C Column 3 of A265466.
%H R. H. Hardin, <a href="/A265461/b265461.txt">Table of n, a(n) for n = 1..210</a>
%e Some solutions for n=4
%e ..0..1..0....0..2..3....0..2..1....0..1..0....0..2..1....0..2..4....0..2..4
%e ..0..1..2....4..2..1....3..2..4....3..2..1....0..2..4....4..3..4....4..3..5
%e ..2..0..1....1..3..2....1..3..4....3..2..4....1..3..2....4..3..4....2..3..2
%e ..1..3..5....2..4..5....1..3..5....1..3..5....4..3..5....1..3..5....5..3..5
%Y Cf. A265466.
%K nonn
%O 1,2
%A _R. H. Hardin_, Dec 09 2015