A220242 T(n,k)=Equals two maps: number of nXk binary arrays indicating the locations of corresponding elements equal to exactly two of their horizontal and vertical neighbors in a random 0..1 nXk array

1, 1, 1, 2, 6, 2, 4, 23, 23, 4, 7, 78, 148, 78, 7, 12, 292, 1131, 1131, 292, 12, 21, 1066, 8127, 14976, 8127, 1066, 21, 37, 3922, 58091, 219617, 219617, 58091, 3922, 37, 65, 14420, 419164, 3101079, 5804389, 3101079, 419164, 14420, 65, 114, 53082, 3016838

Offset

1,4

Comments

Table starts

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

...1.....6......23.......78.......292......1066.....3922.....14420....53082

...2....23.....148.....1131......8127.....58091...419164...3016838.21697096

...4....78....1131....14976....219617...3101079.43677639.613533257

...7...292....8127...219617...5804389.165087351

..12..1066...58091..3101079.165087351

..21..3922..419164.43677639

..37.14420.3016838

..65.53082

.114

Links

R. H. Hardin, Table of n, a(n) for n = 1..59

Example

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

Crossrefs

Column 1 is A005251(n+1)

Sequence in context: A057606 A021385 A085193 * A220375 A220430 A220279

Adjacent sequences: A220239 A220240 A220241 * A220243 A220244 A220245

Keyword

nonn,tabl

Author

R. H. Hardin Dec 08 2012

Status

approved