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%I #5 Aug 12 2016 07:04:20
%S 0,0,0,4,48,584,8096,127296,2241856,43770144,939182976,21981580224,
%T 557527020544,15236894019072,446459870047232,13964134704426752,
%U 464407462322500608
%N Number of nX2 arrays containing 2 copies of 0..n-1 with no equal horizontal, vertical, diagonal or antidiagonal neighbors and new values introduced sequentially from 0.
%C Column 2 of A265421.
%e Some solutions for n=6
%e ..0..1....0..1....0..1....0..1....0..1....0..1....0..1....0..1....0..1....0..1
%e ..2..3....2..3....2..3....2..3....2..3....2..3....2..3....2..3....2..3....2..3
%e ..0..1....1..4....0..4....0..4....4..0....0..4....4..5....1..0....1..4....4..0
%e ..4..5....3..5....5..2....1..5....5..3....5..2....1..2....4..5....3..5....2..5
%e ..3..2....0..4....3..1....2..3....1..4....1..4....4..5....2..3....2..4....3..4
%e ..4..5....5..2....4..5....4..5....5..2....5..3....0..3....4..5....0..5....1..5
%Y Cf. A265421.
%K nonn
%O 1,4
%A _R. H. Hardin_, Dec 08 2015