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A283130 T(n,k)=Number of nXk 0..1 arrays with no 1 equal to more than two of its horizontal and vertical neighbors. 7
2, 4, 4, 8, 16, 8, 16, 57, 57, 16, 32, 209, 378, 209, 32, 64, 768, 2521, 2521, 768, 64, 128, 2816, 16818, 30824, 16818, 2816, 128, 256, 10329, 112276, 376359, 376359, 112276, 10329, 256, 512, 37889, 749447, 4598361, 8402216, 4598361, 749447, 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.......378.........2521..........16818............112276

...16....209......2521........30824.........376359...........4598361

...32....768.....16818.......376359........8402216.........187671790

...64...2816....112276......4598361......187671790........7664347268

..128..10329....749447.....56176300.....4191671248......312996735204

..256..37889...5002276....686250407....93617080958....12781345612180

..512.138980..33388996...8383419717..2090880805128...521941108563948

.1024.509792.222863968.102414019954.46698565884588.21314084605931116

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 9]

k=4: [order 17]

k=5: [order 48]

EXAMPLE

Some solutions for n=4 k=4

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

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

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

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

CROSSREFS

Diagonal is A068471.

Column 1 is A000079.

Sequence in context: A189779 A262338 A283691 * A295716 A282399 A297374

Adjacent sequences:  A283127 A283128 A283129 * A283131 A283132 A283133

KEYWORD

nonn,tabl

AUTHOR

R. H. Hardin, Mar 01 2017

STATUS

approved

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Last modified February 22 08:23 EST 2020. Contains 332118 sequences. (Running on oeis4.)