A220244 Equals two maps: number of nX3 binary arrays indicating the locations of corresponding elements equal to exactly two of their king-move neighbors in a random 0..1 nX3 array

2, 18, 143, 816, 4467, 27192, 158296, 915920, 5443662, 31825008, 185788218, 1094039664, 6406886173, 37509117127, 220173740293, 1290097909772, 7558886967916, 44324041325721

Offset

1,1

Comments

Column 3 of A220247

Links

Table of n, a(n) for n=1..18.

Example

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

Crossrefs

Sequence in context: A216584 A193446 A226733 * A001804 A277182 A052640

Adjacent sequences: A220241 A220242 A220243 * A220245 A220246 A220247

Keyword

nonn

Author

R. H. Hardin Dec 08 2012

Status

approved