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A283522 T(n,k)=Number of nXk 0..1 arrays with no 1 equal to more than three of its horizontal, vertical and antidiagonal neighbors, with the exception of exactly two elements. 7
0, 0, 0, 0, 0, 0, 0, 1, 1, 0, 0, 5, 20, 5, 0, 0, 28, 270, 270, 28, 0, 0, 145, 2763, 5988, 2763, 145, 0, 0, 703, 26662, 113984, 113984, 26662, 703, 0, 0, 3288, 241796, 2032993, 4069571, 2032993, 241796, 3288, 0, 0, 14980, 2115564, 34279720, 136572268 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,12

COMMENTS

Table starts

.0.....0........0..........0.............0................0..................0

.0.....0........1..........5............28..............145................703

.0.....1.......20........270..........2763............26662.............241796

.0.....5......270.......5988........113984..........2032993...........34279720

.0....28.....2763.....113984.......4069571........136572268.........4331276717

.0...145....26662....2032993.....136572268.......8593156813.......510843580504

.0...703...241796...34279720....4331276717.....510843580504.....56913176714906

.0..3288..2115564..558718061..132684847054...29325852758117...6121670820777639

.0.14980.18020972.8877675769.3961612505725.1640229831666201.641300961433598943

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..180

FORMULA

Empirical for column k:

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

k=2: [order 15]

k=3: [order 15] for n>19

k=4: [order 39] for n>43

EXAMPLE

Some solutions for n=4 k=4

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

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

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

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

CROSSREFS

Sequence in context: A302662 A261545 A093482 * A199363 A199588 A030696

Adjacent sequences:  A283519 A283520 A283521 * A283523 A283524 A283525

KEYWORD

nonn,tabl

AUTHOR

R. H. Hardin, Mar 09 2017

STATUS

approved

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Last modified June 28 17:31 EDT 2022. Contains 354907 sequences. (Running on oeis4.)