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%I #6 Dec 18 2015 18:17:59
%S 4,256,205518,2152805235,289315497297232,503617001775793994676
%N Number of n X n 0..3 arrays avoiding the pattern z-2 z-1 z in any row, column, nw-to-se diagonal or ne-to-sw antidiagonal
%C Diagonal of A206838
%e Some solutions for n=5
%e ..3..2..2..1..1....1..3..3..1..2....1..2..0..2..2....0..0..1..3..0
%e ..3..2..0..1..0....0..2..2..1..2....1..0..3..2..2....2..0..3..0..2
%e ..3..3..1..3..2....0..0..1..0..2....0..2..3..3..0....0..3..1..1..2
%e ..2..1..1..2..2....2..0..1..3..2....1..2..0..2..3....0..3..0..1..0
%e ..0..1..3..1..0....0..0..0..0..1....1..1..1..3..3....3..2..2..1..2
%K nonn
%O 1,1
%A _R. H. Hardin_ Feb 13 2012
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