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A295943
T(n,k)=Number of nXk 0..1 arrays with each 1 adjacent to 1 or 3 king-move neighboring 1s.
8
1, 2, 2, 3, 8, 3, 4, 15, 15, 4, 6, 33, 41, 33, 6, 9, 104, 120, 120, 104, 9, 13, 228, 465, 534, 465, 228, 13, 19, 529, 1472, 2976, 2976, 1472, 529, 19, 28, 1469, 4667, 13759, 29081, 13759, 4667, 1469, 28, 41, 3442, 16230, 65009, 187960, 187960, 65009, 16230, 3442
OFFSET
1,2
COMMENTS
Table starts
..1....2.....3.......4........6..........9..........13............19
..2....8....15......33......104........228.........529..........1469
..3...15....41.....120......465.......1472........4667.........16230
..4...33...120.....534.....2976......13759.......65009........325008
..6..104...465....2976....29081.....187960.....1311947......10551008
..9..228..1472...13759...187960....1806751....18443146.....209884397
.13..529..4667...65009..1311947...18443146...279143247....4651767361
.19.1469.16230..325008.10551008..209884397..4651767361..117889600265
.28.3442.53266.1565481.75078015.2194039726.71601077879.2659460386138
LINKS
FORMULA
Empirical for column k:
k=1: a(n) = a(n-1) +a(n-3)
k=2: a(n) = a(n-1) +a(n-2) +9*a(n-3) -4*a(n-4) -4*a(n-5) -4*a(n-6)
k=3: [order 9]
k=4: [order 21]
k=5: [order 55]
EXAMPLE
Some solutions for n=5 k=4
..1..0..0..0. .1..0..0..0. .1..1..0..1. .0..1..0..0. .1..0..0..0
..0..1..1..1. .1..0..0..0. .1..1..0..1. .1..0..0..0. .1..0..0..1
..0..1..0..0. .0..0..1..0. .0..0..0..0. .0..0..1..1. .0..0..0..1
..1..0..0..1. .0..0..1..0. .0..0..0..0. .0..0..0..0. .0..1..0..0
..0..0..0..1. .0..0..0..0. .0..0..0..0. .0..0..1..1. .0..1..0..0
CROSSREFS
Column 1 is A000930(n+1).
Sequence in context: A110985 A153216 A327259 * A296804 A296952 A141611
KEYWORD
nonn,tabl
AUTHOR
R. H. Hardin, Nov 30 2017
STATUS
approved