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A221629
Number of 7Xn arrays with each row a permutation of 1..n having at least as many downsteps as the preceding row
1
1, 8, 29124, 183919920, 15258126049410, 2638115823321645192, 2031241364747667201263520, 3210318128660193294063849550080, 13896214616394139128043246845049514250
OFFSET
1,2
COMMENTS
Row 7 of A221623
LINKS
EXAMPLE
Some solutions for n=3
..1..2..3....1..2..3....2..3..1....3..1..2....1..3..2....3..1..2....1..3..2
..2..3..1....1..3..2....1..3..2....1..3..2....2..1..3....2..3..1....2..1..3
..3..1..2....2..1..3....2..1..3....2..3..1....2..3..1....2..3..1....2..1..3
..3..1..2....1..3..2....3..1..2....2..1..3....2..1..3....3..1..2....1..3..2
..2..1..3....2..3..1....2..1..3....2..1..3....1..3..2....1..3..2....2..3..1
..2..3..1....3..1..2....1..3..2....1..3..2....3..1..2....2..1..3....2..3..1
..2..1..3....1..3..2....2..3..1....3..1..2....2..1..3....2..3..1....2..1..3
CROSSREFS
Sequence in context: A281359 A067070 A115478 * A362280 A013788 A156178
KEYWORD
nonn
AUTHOR
R. H. Hardin Jan 21 2013
STATUS
approved