%I #7 Dec 18 2015 18:18:03
%S 1,10,1059,600426,1820627588,29489112993258,2550050797214882163,
%T 1177059517691274455925664,2899898779178057927709489333244,
%U 38132339745477816025554449167624111270
%N Number of n X n 0..2 arrays with new values 0..2 introduced in row major order and no element equal to more than one of its immediate leftward or upward or left-upward diagonal neighbors
%C Diagonal of A208567
%H R. H. Hardin, <a href="/A208560/b208560.txt">Table of n, a(n) for n = 1..12</a>
%e Some solutions for n=4
%e ..0..0..0..1....0..0..0..0....0..0..1..2....0..0..1..2....0..1..1..0
%e ..1..1..1..0....1..1..1..1....0..2..2..0....2..1..0..0....1..2..2..2
%e ..0..2..2..2....2..2..2..2....2..0..0..1....1..2..1..1....0..1..0..1
%e ..0..1..0..0....0..0..0..0....2..1..2..1....2..1..2..2....2..0..1..2
%K nonn
%O 1,2
%A _R. H. Hardin_ Feb 28 2012
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