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A266306
Number of nX2 arrays containing 2 copies of 0..n-1 with no element 1 greater than its west neighbor modulo n and the upper left element equal to 0.
0
1, 1, 7, 171, 6666, 384360, 30900150, 3314400390, 457970055480, 79281706512960, 16813296291166200, 4287982048554619800
OFFSET
1,3
COMMENTS
Column 2 of A266309.
EXAMPLE
Some solutions for n=4
..0..2....0..2....0..3....0..2....0..0....0..0....0..2....0..3....0..0....0..3
..1..1....1..0....2..0....2..0....1..3....1..3....3..1....0..3....3..1....0..3
..2..0....3..2....2..1....1..3....3..1....1..3....0..3....1..1....1..3....2..1
..3..3....3..1....1..3....1..3....2..2....2..2....2..1....2..2....2..2....2..1
CROSSREFS
Cf. A266309.
Sequence in context: A157203 A178019 A337676 * A332117 A226598 A075599
KEYWORD
nonn
AUTHOR
R. H. Hardin, Dec 26 2015
STATUS
approved