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%I #4 Dec 09 2015 08:58:37
%S 1,1,1,2,9,29,79,220,673,2106,6480,19803,61085,190155,593635,1854310,
%T 5802490,18203576,57227627,180170568,567940927,1792532647,5664324570,
%U 17917857888,56732156348,179781808709,570178314799,1809666098574
%N Number of nX1 0..n+1-2 arrays with upper left zero and lower right n+1-2 and each element differing from its horizontal and vertical neighbors by one or two.
%C Column 1 of A265447.
%H R. H. Hardin, <a href="/A265440/b265440.txt">Table of n, a(n) for n = 1..210</a>
%e All solutions for n=4
%e ..0....0
%e ..1....2
%e ..2....1
%e ..3....3
%Y Cf. A265447.
%K nonn
%O 1,4
%A _R. H. Hardin_, Dec 09 2015