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%I #4 Oct 28 2013 20:29:36
%S 1172,54138,1025430,46599682,801845362,36695929036,625553036008,
%T 28644012159382,487784854592488,22335960353679258,380324726478587580,
%U 17415157060199286942,296532282288946047888,13578285711710490028400
%N Number of (n+3)X(6+3) 0..2 black square subarrays x(i,j) with each element diagonally or antidiagonally next to at least one element with value (x(i,j)+1) mod 3, and upper left element zero
%C Column 6 of A230739
%H R. H. Hardin, <a href="/A230738/b230738.txt">Table of n, a(n) for n = 1..210</a>
%e Some solutions for n=3
%e ..x..0..x..0..x..2..x..0..x....x..0..x..0..x..2..x..2..x
%e ..1..x..1..x..0..x..2..x..1....2..x..1..x..0..x..0..x..1
%e ..x..2..x..0..x..1..x..2..x....x..2..x..0..x..1..x..2..x
%e ..0..x..2..x..1..x..0..x..2....0..x..2..x..2..x..0..x..1
%e ..x..1..x..1..x..2..x..0..x....x..1..x..2..x..1..x..2..x
%e ..0..x..0..x..1..x..1..x..2....0..x..0..x..1..x..1..x..1
%K nonn
%O 1,1
%A _R. H. Hardin_, Oct 28 2013