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A283415 T(n,k)=Number of nXk 0..1 arrays with no 1 equal to more than three of its horizontal, vertical and antidiagonal neighbors. 8
2, 4, 4, 8, 16, 8, 16, 61, 61, 16, 32, 236, 416, 236, 32, 64, 912, 2944, 2944, 912, 64, 128, 3525, 20744, 39268, 20744, 3525, 128, 256, 13624, 146228, 519252, 519252, 146228, 13624, 256, 512, 52656, 1030788, 6865368, 12806920, 6865368, 1030788, 52656, 512 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Table starts

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

....4.....16........61..........236.............912..............3525

....8.....61.......416.........2944...........20744............146228

...16....236......2944........39268..........519252...........6865368

...32....912.....20744.......519252........12806920.........315717408

...64...3525....146228......6865368.......315717408.......14511646624

..128..13624...1030788.....90803472......7790355688......668024193788

..256..52656...7266120...1200890168....192182078748....30738576483000

..512.203513..51219756..15882218184...4741143038544..1414483814666200

.1024.786568.361053936.210047690772.116964083503632.65089911870493672

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..238

FORMULA

Empirical for column k:

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

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

k=3: a(n) = 5*a(n-1) +13*a(n-2) +10*a(n-3) +a(n-4) +2*a(n-5) for n>7

k=4: [order 13] for n>15

k=5: [order 37] for n>39

k=6: [order 72] for n>77

EXAMPLE

Some solutions for n=4 k=4

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

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

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

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

CROSSREFS

Column 1 is A000079.

Sequence in context: A282399 A297374 A297102 * A283857 A227442 A282316

Adjacent sequences:  A283412 A283413 A283414 * A283416 A283417 A283418

KEYWORD

nonn,tabl

AUTHOR

R. H. Hardin, Mar 07 2017

STATUS

approved

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Last modified February 28 11:08 EST 2020. Contains 332323 sequences. (Running on oeis4.)