%I #6 Dec 18 2015 18:17:56
%S 0,16,378,91223,136175057,1492809994673
%N Number of n X n 0..3 arrays with rows and columns lexicographically nondecreasing and every element equal to at least one horizontal or vertical neighbor
%C Diagonal of A201625
%e Some solutions for n=4
%e ..0..0..3..3....0..0..0..1....0..0..1..1....0..0..1..1....0..0..2..2
%e ..2..2..1..3....0..2..3..1....1..2..2..2....0..3..0..1....3..3..1..1
%e ..2..2..1..3....1..2..3..1....1..2..3..3....0..3..0..2....3..3..1..2
%e ..3..3..1..1....1..2..3..3....3..3..1..1....1..1..0..2....3..3..2..2
%K nonn
%O 1,2
%A _R. H. Hardin_ Dec 03 2011
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