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%I #5 Aug 12 2016 06:54:17
%S 0,6,6,672,4734,177048,4131792,132137160,4330697670,144754955796
%N Number of 4Xn arrays containing n copies of 0..4-1 with every element equal to at least one diagonal or antidiagonal neighbor and the top left element equal to 0.
%C Row 4 of A268142.
%e Some solutions for n=4
%e ..0..0..2..1....0..3..2..3....0..1..1..2....0..3..0..3....0..1..2..3
%e ..0..0..1..2....3..0..3..2....1..0..2..1....3..0..3..0....1..0..3..2
%e ..3..3..2..1....2..0..1..1....3..3..2..0....2..1..2..1....0..3..2..1
%e ..3..3..1..2....0..2..1..1....3..3..0..2....1..2..1..2....3..0..1..2
%Y Cf. A268142.
%K nonn
%O 1,2
%A _R. H. Hardin_, Jan 27 2016