%I #5 Aug 12 2016 07:04:22
%S 1,0,0,8,411,30362,2742512,317221226,46165940578,8303305172988,
%T 1813340078934264
%N Number of nX2 arrays containing 2 copies of 0..n-1 with no element 1 greater than its west, southwest or northwest neighbor modulo n and the upper left element equal to 0.
%C Column 2 of A267163.
%e All solutions for n=4
%e ..0..0....0..3....0..0....0..0....0..2....0..2....0..2....0..3
%e ..2..2....3..2....1..3....2..2....2..0....0..2....3..3....1..0
%e ..3..1....2..1....3..1....3..1....1..1....3..3....1..1....2..1
%e ..3..1....1..0....2..2....1..3....3..3....1..1....2..0....3..2
%Y Cf. A267163.
%K nonn
%O 1,4
%A _R. H. Hardin_, Jan 11 2016