A207128 Number of n X n 0..3 arrays avoiding the pattern z z+1 z in any row or column

4, 256, 197144, 1981367324, 264331974554825, 466503557360950708206

Offset

1,1

Comments

Diagonal of A207134

Links

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

Example

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

Crossrefs

Sequence in context: A207576 A209086 A207051 * A223579 A206832 A206894

Adjacent sequences: A207125 A207126 A207127 * A207129 A207130 A207131

Keyword

nonn

Author

R. H. Hardin Feb 15 2012

Status

approved