A183623 Number of (n+1)X(n+1) 0..2 arrays with every 2X2 subblock summing to 4

19, 87, 355, 1383, 5299, 20247, 77635, 299463, 1162579, 4540407

Offset

1,1

Comments

Diagonal of A183632

Links

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

Example

Some solutions for 3X3
..1..2..0....0..2..0....1..2..0....2..0..1....1..1..0....0..1..0....0..1..1
..0..1..1....2..0..2....1..0..2....0..2..1....0..2..1....1..2..1....2..1..1
..2..1..1....1..1..1....2..1..1....2..0..1....1..1..0....0..1..0....1..0..2

Crossrefs

Sequence in context: A039609 A063496 A027848 * A039454 A142089 A174819

Adjacent sequences: A183620 A183621 A183622 * A183624 A183625 A183626

Keyword

nonn

Author

R. H. Hardin Jan 06 2011

Status

approved