A221255 T(n,k)=Number of nXk arrays of occupancy after each element moves to some horizontal or antidiagonal neighbor, with no occupancy greater than 2

0, 1, 0, 2, 4, 0, 4, 8, 16, 0, 8, 81, 30, 64, 0, 16, 392, 2116, 112, 256, 0, 32, 2500, 22268, 58081, 418, 1024, 0, 64, 14112, 488601, 1319409, 1612900, 1560, 4096, 0, 128, 83521, 7356420, 103489929, 78633756, 44903401, 5822, 16384, 0, 256, 484128, 132273001

Offset

1,4

Comments

Table starts

.0.....1.....2...........4..............8.................16

.0.....4.....8..........81............392...............2500

.0....16....30........2116..........22268.............488601

.0....64...112.......58081........1319409..........103489929

.0...256...418.....1612900.......78633756........22466712321

.0..1024..1560....44903401.....4684821704......4919350997521

.0..4096..5822..1250753956...278802326676...1080371161000000

.0.16384.21728.34842328921.16577412686597.237502965724417600

Even columns are perfect squares

Links

R. H. Hardin, Table of n, a(n) for n = 1..126

Example

Some solutions for n=3 k=4
..1..2..1..0....0..2..2..0....0..2..2..1....0..2..2..1....1..1..0..1
..0..2..1..2....0..2..1..0....0..1..1..1....1..0..1..1....1..1..1..1
..2..0..1..0....2..1..1..1....2..1..1..0....1..1..1..1....1..1..2..1

Crossrefs

Column 2 is A000302(n-1)

Column 3 is A052530

Sequence in context: A115368 A086932 A331762 * A341862 A256487 A079985

Adjacent sequences: A221252 A221253 A221254 * A221256 A221257 A221258

Keyword

nonn,tabl

Author

R. H. Hardin Jan 06 2013

Status

approved