A221294 Equals two maps: number of 6Xn binary arrays indicating the locations of corresponding elements equal to exactly two of their horizontal and antidiagonal neighbors in a random 0..3 6Xn array.
1, 351, 19996, 1686304, 143511784, 10344276279
Offset: 1
Keywords
Examples
Some solutions for n=3 ..0..1..0....0..0..0....0..0..1....0..0..1....0..0..1....0..1..1....0..1..0 ..0..1..1....0..0..0....0..1..0....1..0..1....0..1..0....0..1..0....1..1..0 ..1..0..1....1..0..0....0..0..0....0..0..0....1..1..0....0..1..1....0..0..1 ..0..0..0....0..1..0....1..1..0....0..0..1....0..0..0....0..1..0....0..1..0 ..0..1..1....0..0..0....0..1..1....1..0..1....1..1..0....1..1..0....1..1..0 ..1..1..0....1..1..0....1..1..0....0..1..0....1..1..0....0..0..0....1..0..0
Comments