A224256 Number of n X n 0..2 arrays with rows, diagonals and antidiagonals unimodal and columns nondecreasing.
3, 36, 648, 12467, 238366, 4480391, 83124099, 1530419762, 28072690614, 514262753781, 9420094252771
Offset: 1
Examples
Some solutions for n=3: ..0..2..0....0..1..0....0..0..0....1..1..0....1..2..0....2..1..1....0..1..0 ..0..2..0....0..1..0....2..0..0....2..2..1....2..2..0....2..2..2....2..2..2 ..0..2..0....1..1..2....2..1..0....2..2..2....2..2..0....2..2..2....2..2..2
Crossrefs
Main diagonal of A224262.
Extensions
Name corrected by Andrew Howroyd, Mar 18 2025