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A223943
Number of n X n 0..1 arrays with diagonals and antidiagonals unimodal and rows nondecreasing.
0
2, 9, 54, 321, 1821, 9919, 52532, 272997, 1401993, 7150718, 36352875, 184670276, 938969921, 4783571827, 24431153268, 125119394092
OFFSET
1,1
COMMENTS
Diagonal of A223949.
EXAMPLE
Some solutions for n=3
..0..1..1....0..0..0....0..0..0....0..1..1....0..0..0....0..0..0....0..1..1
..0..0..0....0..0..1....1..1..1....0..0..1....0..0..1....0..1..1....0..0..0
..0..0..0....0..0..1....0..0..1....0..0..1....0..0..0....0..0..1....0..0..1
CROSSREFS
Cf. A223949.
Sequence in context: A233338 A360454 A073986 * A371698 A241125 A370474
KEYWORD
nonn
AUTHOR
R. H. Hardin, Mar 29 2013
STATUS
approved