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%I #5 Aug 12 2016 07:04:22
%S 1,0,1,27,555,24981,1825761,184975696,24714858112,4188322485532,
%T 875632389820566
%N Number of nX2 arrays containing 2 copies of 0..n-1 with no element 1 greater than its north, west or southeast neighbor modulo n and the upper left element equal to 0.
%C Column 2 of A267546.
%e Some solutions for n=4
%e ..0..2....0..2....0..2....0..2....0..2....0..3....0..2....0..2....0..3....0..3
%e ..2..1....3..1....0..2....0..2....3..1....2..1....3..2....3..1....2..1....3..1
%e ..1..0....2..1....3..1....3..1....3..1....0..3....1..1....1..0....1..3....2..1
%e ..3..3....0..3....3..1....1..3....2..0....2..1....0..3....3..2....0..2....2..0
%Y Cf. A267546.
%K nonn
%O 1,4
%A _R. H. Hardin_, Jan 16 2016