A207234 Number of nX7 0..2 arrays avoiding the patterns z z+1 z or z z-1 z in any row, column, diagonal or antidiagonal.

1121, 1256641, 191801477, 68168506265, 22315875854161, 6288613378797777, 1735838281998728881, 487608742366796981785

Offset

1,1

Comments

Column 7 of A207235

Links

Table of n, a(n) for n=1..8.

Example

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

Crossrefs

Sequence in context: A028464 A225995 A122052 * A207227 A207014 A203189

Adjacent sequences: A207231 A207232 A207233 * A207235 A207236 A207237

Keyword

nonn

Author

R. H. Hardin, Feb 16 2012

Status

approved