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%I #4 Mar 11 2014 15:28:54
%S 1,2,868,135766,821135900,5427557363908,486439997897622259,
%T 105891766683961733641397
%N Number of (n+1)X(n+1) 0..3 arrays with no element equal to all horizontal neighbors or unequal to all vertical neighbors, and new values 0..3 introduced in row major order
%C Diagonal of A239155
%e Some solutions for n=4
%e ..0..1..0..2..1....0..1..1..2..3....0..1..2..3..2....0..1..2..0..3
%e ..0..1..0..2..1....0..1..1..2..3....0..1..2..3..2....0..1..2..0..3
%e ..3..1..3..2..3....0..2..1..2..3....0..1..3..3..2....0..1..0..1..0
%e ..3..1..3..2..3....3..2..2..3..2....0..2..3..0..2....0..2..0..1..0
%e ..3..1..3..2..3....3..2..2..3..2....0..2..3..0..2....0..2..0..1..0
%K nonn
%O 1,2
%A _R. H. Hardin_, Mar 11 2014