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%I #8 May 04 2021 13:39:17
%S 4,256,180446,1382766472,120305843593958,118056098980249594900
%N Number of n X n 0..3 arrays avoiding the pattern z z+1 z in any row, column, diagonal or antidiagonal.
%C Diagonal of A206797.
%e Some solutions for n=4
%e ..0..1..1..3....1..0..0..0....1..1..1..3....3..2..2..1....0..1..3..0
%e ..2..2..1..2....0..3..1..2....3..3..2..0....1..2..2..0....2..0..3..0
%e ..2..2..3..3....1..1..1..3....0..2..2..2....1..3..1..3....2..0..3..1
%e ..0..3..3..0....1..3..3..1....3..1..0..0....1..1..3..3....1..2..0..2
%Y Cf. A206797.
%K nonn
%O 1,1
%A _R. H. Hardin_ Feb 12 2012