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A201270
Number of n X n 0..2 arrays with every row and column nondecreasing rightwards and downwards, and the number of instances of each value within one of each other.
1
1, 3, 5, 7, 85, 556, 1260, 27008, 215577, 613916, 16442049, 152673459, 487975060, 14392411292, 144918917509, 496264541787, 15559415313705, 165127072154120, 592098075114238, 19339952787547252, 212870280758956694, 788675446037414831, 26535438036570486429, 300014957716483809886
OFFSET
0,2
EXAMPLE
Some solutions for n=5
..0..0..0..0..2....0..0..0..0..2....0..0..0..0..0....0..0..0..0..0
..0..0..1..2..2....0..0..1..1..2....0..0..0..1..1....0..0..1..2..2
..0..1..1..2..2....0..1..1..2..2....1..1..1..1..1....0..1..1..2..2
..0..1..1..2..2....0..1..1..2..2....1..2..2..2..2....1..1..1..2..2
..1..1..1..2..2....1..1..1..2..2....2..2..2..2..2....1..1..1..2..2
CROSSREFS
Main diagonal of A201277.
Sequence in context: A306573 A254925 A153138 * A160360 A082697 A051345
KEYWORD
nonn
AUTHOR
R. H. Hardin, Nov 29 2011
EXTENSIONS
a(0)=1 prepended and a(19)-a(23) added by Alois P. Heinz, Mar 17 2024
STATUS
approved