A186489 Number of (n+1)X(n+1) 0..7 arrays with every 2X2 subblock commuting with each of its horizontal and vertical 2X2 subblock neighbors

4096, 4834, 269126, 1024481, 21122896, 70300633, 1381305433, 5019710665, 92758821369, 358905890921, 6225263778969, 25517863738777, 418350075763113, 1809120677086713, 28157232600156937, 127921801557860825

Offset

1,1

Comments

Diagonal of A186490

Links

R. H. Hardin, Table of n, a(n) for n = 1..20

Example

Some solutions for 3X3
..6..0..6....7..4..0....3..6..3....3..5..0....6..7..0....5..4..0....5..0..0
..0..6..0....1..0..4....6..3..6....1..0..5....5..0..7....0..0..4....0..0..0
..3..0..6....0..1..5....3..6..3....0..1..4....0..5..7....0..0..3....0..0..0

Crossrefs

Sequence in context: A223601 A186490 A223694 * A221261 A069273 A043424

Adjacent sequences: A186486 A186487 A186488 * A186490 A186491 A186492

Keyword

nonn

Author

R. H. Hardin Feb 22 2011

Status

approved