A186453 Number of (n+1)X(n+1) binary arrays with every 2X2 subblock commuting with each of its horizontal and vertical 2X2 subblock neighbors

16, 30, 111, 309, 797, 1693, 4121, 9477, 22933, 52197, 122109, 277217, 642629, 1463845, 3375245, 7698781, 17693113, 40404005, 92697797, 211861205, 485587357, 1110399969, 2543583205, 5818446165, 13323806077, 30484799837, 69794079385

Offset

1,1

Comments

Diagonal of A186462

Links

R. H. Hardin, Table of n, a(n) for n = 1..39

Example

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

Crossrefs

Sequence in context: A183372 A308026 A145581 * A129617 A221257 A194122

Adjacent sequences: A186450 A186451 A186452 * A186454 A186455 A186456

Keyword

nonn

Author

R. H. Hardin Feb 22 2011

Status

approved