A206789 Number of n X n 0..3 arrays avoiding the pattern z z+1 z in any row, column, diagonal or antidiagonal.

4, 256, 180446, 1382766472, 120305843593958, 118056098980249594900

Offset

1,1

Comments

Diagonal of A206797.

Links

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

Example

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

Crossrefs

Cf. A206797.

Sequence in context: A223658 A207529 A206968 * A206961 A206569 A207576

Adjacent sequences: A206786 A206787 A206788 * A206790 A206791 A206792

Keyword

nonn

Author

R. H. Hardin Feb 12 2012

Status

approved