A222787 Number of n X n 0..3 arrays with exactly floor(n X n/2) elements unequal to at least one horizontal or antidiagonal neighbor, with new values introduced in row major 0..3 order

1, 3, 34, 5896, 1615706, 8113737592, 39461160617203, 3271351045573714833, 264112864034567015904268

Offset

1,2

Comments

Diagonal of A222794

Links

Table of n, a(n) for n=1..9.

Example

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

Crossrefs

Sequence in context: A194891 A194892 A182382 * A180126 A214854 A054287

Adjacent sequences: A222784 A222785 A222786 * A222788 A222789 A222790

Keyword

nonn

Author

R. H. Hardin Mar 05 2013

Status

approved