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A295716 T(n,k)=Number of nXk 0..1 arrays with each 1 horizontally or vertically adjacent to 0, 1, 2 or 4 1s. 7
2, 4, 4, 8, 16, 8, 16, 57, 57, 16, 32, 209, 385, 209, 32, 64, 768, 2580, 2580, 768, 64, 128, 2816, 17364, 31985, 17364, 2816, 128, 256, 10329, 116902, 396571, 396571, 116902, 10329, 256, 512, 37889, 786804, 4919857, 9056598, 4919857, 786804, 37889, 512 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Table starts

...2......4........8.........16............32..............64

...4.....16.......57........209...........768............2816

...8.....57......385.......2580.........17364..........116902

..16....209.....2580......31985........396571.........4919857

..32....768....17364.....396571.......9056598.......206899873

..64...2816...116902....4919857.....206899873......8705322572

.128..10329...786804...61023234....4725935539....366212961052

.256..37889..5295555..756896741..107948235688..15405701771951

.512.138980.35642190.9388238587.2465745246117.648089607011677

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..264

FORMULA

Empirical for column k:

k=1: a(n) = 2*a(n-1)

k=2: a(n) = 3*a(n-1) +2*a(n-2) +2*a(n-3) -a(n-4) -a(n-5)

k=3: [order 12]

k=4: [order 28]

k=5: [order 76]

EXAMPLE

Some solutions for n=4 k=4

..0..0..0..0....0..0..1..1....0..1..0..0....0..0..1..1....0..1..0..1

..0..1..0..0....1..0..0..1....0..0..0..0....0..0..0..0....1..1..1..0

..1..0..1..1....0..0..1..0....1..0..1..1....0..0..1..1....0..1..0..1

..0..1..1..0....0..0..1..0....1..0..1..0....1..0..0..1....1..0..1..1

CROSSREFS

Column 1 is A000079.

Column 2 is A283124.

Sequence in context: A262338 A283691 A283130 * A282399 A297374 A297102

Adjacent sequences:  A295713 A295714 A295715 * A295717 A295718 A295719

KEYWORD

nonn,tabl

AUTHOR

R. H. Hardin, Nov 26 2017

STATUS

approved

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Last modified November 30 09:54 EST 2021. Contains 349419 sequences. (Running on oeis4.)