A220374 Equals two maps: number of nX4 binary arrays indicating the locations of corresponding elements equal to exactly two of their horizontal and vertical neighbors in a random 0..2 nX4 array

4, 94, 2095, 39780, 722126, 12480964, 209958887, 3466406061

Offset

1,1

Comments

Column 4 of A220375

Links

Table of n, a(n) for n=1..8.

Example

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

Crossrefs

Sequence in context: A116291 A061992 A221389 * A220429 A210857 A220682

Adjacent sequences: A220371 A220372 A220373 * A220375 A220376 A220377

Keyword

nonn

Author

R. H. Hardin Dec 13 2012

Status

approved