A203331 Number of n X n 0..5 arrays with every nonzero element less than or equal to at least two horizontal and vertical neighbors.

1, 6, 1311, 2224079, 40063085907, 11867803667695158

Offset

1,2

Comments

Diagonal of A203338.

Links

Table of n, a(n) for n=1..6.

Example

Some solutions for n=4
..2..3..4..4....5..5..2..0....5..5..4..2....2..3..3..3....2..4..4..4
..5..5..5..4....5..5..5..2....5..5..4..3....2..3..3..3....3..4..3..4
..5..0..5..4....0..2..5..5....0..3..5..5....1..0..2..2....4..4..0..4
..5..5..5..1....0..0..5..5....0..0..5..5....1..1..1..0....4..4..4..4

Crossrefs

Cf. A203338.

Sequence in context: A209590 A076781 A055306 * A172625 A066037 A279924

Adjacent sequences: A203328 A203329 A203330 * A203332 A203333 A203334

Keyword

nonn

Author

R. H. Hardin, Dec 31 2011

Status

approved