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%I #4 Feb 16 2014 06:48:13
%S 256,10014,369068,25087700,3450339192,713207137992,276807823136806,
%T 191404026313142728,237221109913547184542
%N Number of (n+1)X(n+1) 0..3 arrays with the upper median of every 2X2 subblock differing from its horizontal and vertical neighbors by exactly one
%C Diagonal of A237974
%e Some solutions for n=2
%e ..1..1..3....2..1..3....1..1..1....1..2..1....1..1..2....2..3..3....2..1..0
%e ..0..0..2....3..1..3....3..2..0....0..1..3....2..0..2....1..2..2....2..1..1
%e ..3..0..1....0..1..2....3..2..0....0..0..1....2..1..0....1..1..3....3..3..2
%K nonn
%O 1,1
%A _R. H. Hardin_, Feb 16 2014