A220247 T(n,k)=Equals two maps: number of nXk binary arrays indicating the locations of corresponding elements equal to exactly two of their king-move neighbors in a random 0..1 nXk array

1, 1, 1, 2, 5, 2, 4, 18, 18, 4, 7, 37, 143, 37, 7, 12, 85, 816, 816, 85, 12, 21, 184, 4467, 7140, 4467, 184, 21, 37, 393, 27192, 64258, 64258, 27192, 393, 37, 65, 826, 158296, 660677, 942945, 660677, 158296, 826, 65, 114, 1726, 915920, 6228324, 16925474

Offset

1,4

Comments

Table starts

...1....1.......2........4.........7........12........21.......37........65

...1....5......18.......37........85.......184.......393......826......1726

...2...18.....143......816......4467.....27192....158296...915920...5443662

...4...37.....816.....7140.....64258....660677...6228324.59704733.580593280

...7...85....4467....64258....942945..16925474.267978208

..12..184...27192...660677..16925474.535851061

..21..393..158296..6228324.267978208

..37..826..915920.59704733

..65.1726.5443662

.114.3568

.200

Links

R. H. Hardin, Table of n, a(n) for n = 1..70

Example

Some solutions for n=3 k=4
..1..1..0..0....0..0..1..0....0..1..0..0....1..0..1..0....0..0..1..1
..1..0..0..0....0..0..1..0....0..0..1..1....0..1..0..0....0..0..0..0
..1..0..1..0....0..0..0..1....0..0..0..0....0..1..0..0....0..1..0..1

Crossrefs

Column 1 is A005251(n+1)

Sequence in context: A216625 A122581 A151871 * A220319 A220342 A221676

Adjacent sequences: A220244 A220245 A220246 * A220248 A220249 A220250

Keyword

nonn,tabl

Author

R. H. Hardin Dec 08 2012

Status

approved