A233019 Number of n X n 0..3 arrays with no element x(i,j) adjacent to value 3-x(i,j) horizontally, vertically, diagonally or antidiagonally, and top left element zero.
1, 15, 849, 179999, 149128385, 487651369463, 6338787392715565, 328918675019714663095, 68332288847776936953486283, 56955693489584720827393016043135
Offset: 1
Keywords
Examples
Some solutions for n=4 ..0..0..2..3....0..0..2..3....0..0..2..2....0..2..2..0....0..2..0..0 ..0..2..2..2....2..0..2..2....2..0..0..2....0..2..0..2....2..0..2..2 ..0..2..3..3....2..2..0..2....0..0..0..0....0..2..2..2....0..2..0..2 ..0..2..2..3....0..0..2..2....0..0..0..0....0..2..0..2....2..2..0..0
Links
- R. H. Hardin, Table of n, a(n) for n = 1..11
Comments