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%I #4 Dec 09 2015 09:00:06
%S 1,1,2,53,455,2218,9702,59956,444998,2915881,16984838,100144150,
%T 638465320,4169033187,26450244798,164385366814,1031338919194,
%U 6581317747223,42129509368387,268046060285802,1701181410512570
%N Number of nX2 0..n+2-2 arrays with upper left zero and lower right n+2-2 and each element differing from its horizontal and vertical neighbors by one or two.
%C Column 2 of A265447.
%H R. H. Hardin, <a href="/A265441/b265441.txt">Table of n, a(n) for n = 1..210</a>
%e Some solutions for n=4
%e ..0..2....0..2....0..2....0..1....0..2....0..1....0..2....0..2....0..2....0..2
%e ..2..3....2..4....2..1....2..3....2..1....1..2....2..1....2..0....2..1....2..0
%e ..4..2....1..2....1..3....0..2....0..2....2..3....4..3....4..2....1..2....0..2
%e ..3..4....3..4....2..4....2..4....2..4....3..4....3..4....3..4....2..4....2..4
%Y Cf. A265447.
%K nonn
%O 1,3
%A _R. H. Hardin_, Dec 09 2015