A224051 Number of n X n 0..2 arrays with rows and columns unimodal and antidiagonals nondecreasing

3, 54, 1232, 27246, 568107, 11231300, 212819499, 3903149379, 69818587635, 1225169731998

Offset

1,1

Comments

Diagonal of A224057

Links

Table of n, a(n) for n=1..10.

Example

Some solutions for n=3
..2..1..1....0..1..0....0..0..0....2..1..0....1..1..0....2..0..0....0..0..0
..2..1..1....1..1..1....2..2..0....2..0..0....1..2..0....2..1..1....0..0..2
..1..2..1....1..1..0....2..2..2....0..0..0....2..2..1....2..2..1....1..2..0

Crossrefs

Sequence in context: A223926 A003776 A222203 * A355365 A317663 A323325

Adjacent sequences: A224048 A224049 A224050 * A224052 A224053 A224054

Keyword

nonn

Author

R. H. Hardin Mar 30 2013

Status

approved