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A282647
T(n,k)=Number of nXk 0..1 arrays with no 1 equal to more than one of its king-move neighbors.
8
2, 4, 4, 7, 11, 7, 13, 27, 27, 13, 24, 76, 99, 76, 24, 44, 201, 413, 413, 201, 44, 81, 537, 1601, 2638, 1601, 537, 81, 149, 1444, 6349, 15460, 15460, 6349, 1444, 149, 274, 3859, 25153, 92817, 133118, 92817, 25153, 3859, 274, 504, 10339, 99287, 557439, 1190848
OFFSET
1,1
COMMENTS
Table starts
...2.....4.......7........13.........24...........44.............81
...4....11......27........76........201..........537...........1444
...7....27......99.......413.......1601.........6349..........25153
..13....76.....413......2638......15460........92817.........557439
..24...201....1601.....15460.....133118......1190848.......10614316
..44...537....6349.....92817....1190848.....15985259......213392087
..81..1444...25153....557439...10614316....213392087.....4257307148
.149..3859...99287...3332685...94161619...2835418176....84514081303
.274.10339..392907..19979228..838433062..37825158151..1685475197497
.504.27692.1553391.119669673.7454215075.503735487244.33544066527869
LINKS
FORMULA
Empirical for column k:
k=1: a(n) = a(n-1) +a(n-2) +a(n-3)
k=2: a(n) = a(n-1) +3*a(n-2) +4*a(n-3)
k=3: a(n) = 2*a(n-1) +6*a(n-2) +8*a(n-3) -5*a(n-4) +2*a(n-5) -2*a(n-6)
k=4: [order 9]
k=5: [order 21]
k=6: [order 30]
k=7: [order 66]
EXAMPLE
Some solutions for n=4 k=4
..0..0..0..1. .0..0..0..0. .1..0..0..1. .0..1..0..0. .0..1..0..0
..0..1..0..1. .1..0..1..0. .0..1..0..1. .0..0..0..0. .0..0..0..1
..1..0..0..0. .0..0..1..0. .0..0..0..0. .1..0..0..1. .0..0..0..1
..0..0..0..0. .1..0..0..0. .0..1..0..0. .1..0..0..0. .1..0..0..0
CROSSREFS
Column 1 is A000073(n+3).
Sequence in context: A238493 A362937 A268781 * A269089 A282862 A296578
KEYWORD
nonn,tabl
AUTHOR
R. H. Hardin, Feb 20 2017
STATUS
approved