A220318 Equals two maps: number of n X 4 binary arrays indicating the locations of corresponding elements equal to exactly two of their king-move neighbors in a random 0..2 n X 4 array.

4, 89, 3167, 56819, 984087, 16290350, 264901883

Offset

1,1

Comments

Column 4 of A220319.

Links

Table of n, a(n) for n=1..7.

Example

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

Crossrefs

Cf. A220319.

Sequence in context: A235858 A262409 A183880 * A220341 A184955 A205295

Adjacent sequences: A220315 A220316 A220317 * A220319 A220320 A220321

Keyword

nonn

Author

R. H. Hardin, Dec 10 2012

Status

approved