A220797 Equals two maps: number of 4Xn binary arrays indicating the locations of corresponding elements equal to exactly two of their horizontal, diagonal and antidiagonal neighbors in a random 0..2 4Xn array

1, 94, 1224, 32507, 602536, 10731537, 183846017

Offset

1,2

Comments

Row 4 of A220794

Links

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

Example

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

Crossrefs

Sequence in context: A196892 A093294 A107613 * A220961 A218648 A278321

Adjacent sequences: A220794 A220795 A220796 * A220798 A220799 A220800

Keyword

nonn

Author

R. H. Hardin Dec 21 2012

Status

approved