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A305089
T(n,k)=Number of nXk 0..1 arrays with every element unequal to 1, 2, 3, 6 or 7 king-move adjacent elements, with upper left element zero.
7
0, 1, 1, 1, 7, 1, 2, 14, 14, 2, 3, 33, 22, 33, 3, 5, 70, 34, 34, 70, 5, 8, 157, 182, 91, 182, 157, 8, 13, 346, 438, 352, 352, 438, 346, 13, 21, 769, 920, 372, 3384, 372, 920, 769, 21, 34, 1710, 3431, 1016, 15814, 15814, 1016, 3431, 1710, 34, 55, 3813, 9510, 3474, 39016
OFFSET
1,5
COMMENTS
Table starts
..0....1....1....2.......3........5.........8.........13...........21
..1....7...14...33......70......157.......346........769.........1710
..1...14...22...34.....182......438.......920.......3431.........9510
..2...33...34...91.....352......372......1016.......3474.........4945
..3...70..182..352....3384....15814.....39016.....211725......1172982
..5..157..438..372...15814...101803....285422....3531950.....30133609
..8..346..920.1016...39016...285422....630306...12378708....108542087
.13..769.3431.3474..211725..3531950..12378708..219093711...4455522372
.21.1710.9510.4945.1172982.30133609.108542087.4455522372.154688671720
LINKS
FORMULA
Empirical for column k:
k=1: a(n) = a(n-1) +a(n-2)
k=2: a(n) = 2*a(n-1) +3*a(n-2) -2*a(n-3) -6*a(n-4) -4*a(n-5) for n>6
k=3: [order 14] for n>16
k=4: [order 19] for n>24
k=5: [order 97] for n>101
EXAMPLE
Some solutions for n=5 k=4
..0..1..0..0. .0..1..1..0. .0..1..1..0. .0..1..0..0. .0..1..1..1
..1..1..0..1. .1..1..1..1. .0..1..0..0. .1..0..1..1. .1..1..0..0
..1..1..1..1. .1..1..0..1. .0..0..0..0. .1..1..1..1. .1..1..1..0
..0..0..1..1. .1..0..1..1. .0..0..1..0. .1..1..0..1. .0..1..1..1
..1..0..1..0. .0..1..1..0. .1..1..0..0. .0..1..0..0. .0..0..1..0
CROSSREFS
Column 1 is A000045(n-1).
Column 2 is A304143.
Sequence in context: A119506 A304149 A305489 * A316740 A304019 A305367
KEYWORD
nonn,tabl
AUTHOR
R. H. Hardin, May 25 2018
STATUS
approved