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%I #4 Nov 04 2013 07:35:43
%S 1,9,308,27171,6794904,4509445997,8349491299560,41122867660973690,
%T 564457878709147238868,20611335365445954476620968,
%U 2097381737046509117354544061212,567772314049031950964995256826728363
%N Number of (n+1)X(n+1) black-square subarrays of 0..2 arrays with no element equal to a strict majority of its diagonal and antidiagonal neighbors, with values 0..2 introduced in row major order
%C Diagonal of A231137
%e Some solutions for n=4
%e ..x..0..x..1..x....x..0..x..1..x....x..0..x..0..x....x..0..x..0..x
%e ..2..x..0..x..2....1..x..2..x..2....1..x..0..x..1....0..x..1..x..2
%e ..x..0..x..1..x....x..0..x..0..x....x..1..x..1..x....x..2..x..1..x
%e ..1..x..0..x..0....2..x..1..x..2....0..x..2..x..0....1..x..2..x..1
%e ..x..2..x..1..x....x..0..x..1..x....x..2..x..2..x....x..0..x..0..x
%K nonn
%O 1,2
%A _R. H. Hardin_, Nov 04 2013