A233067 Number of n X n 0..3 arrays with no element x(i,j) adjacent to value 3-x(i,j) horizontally, antidiagonally or vertically, top left element zero, and 1 appearing before 2 in row major order

1, 9, 582, 164495, 194998895, 975239425635, 20656955820980290, 1857471420698911806909, 710147877110621514637926027, 1155599363385647621950232861908393

Offset

1,2

Comments

Diagonal of A233073

Links

R. H. Hardin, Table of n, a(n) for n = 1..11

Example

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

Crossrefs

Sequence in context: A064560 A264121 A095968 * A067320 A061611 A238609

Adjacent sequences: A233064 A233065 A233066 * A233068 A233069 A233070

Keyword

nonn

Author

R. H. Hardin, Dec 03 2013

Status

approved