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A304058
T(n,k)=Number of nXk 0..1 arrays with every element unequal to 1, 2, 4 or 5 king-move adjacent elements, with upper left element zero.
8
0, 1, 1, 1, 3, 1, 2, 11, 11, 2, 3, 10, 6, 10, 3, 5, 51, 18, 18, 51, 5, 8, 165, 32, 26, 32, 165, 8, 13, 306, 60, 155, 155, 60, 306, 13, 21, 993, 124, 427, 596, 427, 124, 993, 21, 34, 2867, 288, 1122, 1641, 1641, 1122, 288, 2867, 34, 55, 6818, 598, 4109, 5415, 3434, 5415
OFFSET
1,5
COMMENTS
Table starts
..0....1...1.....2......3......5.......8.......13........21.........34
..1....3..11....10.....51....165.....306......993......2867.......6818
..1...11...6....18.....32.....60.....124......288.......598.......1266
..2...10..18....26....155....427....1122.....4109.....13836......42480
..3...51..32...155....596...1641....5415....30207....124598.....500772
..5..165..60...427...1641...3434...13624....69126....260517....1102813
..8..306.124..1122...5415..13624...77360...478889...2630794...17166221
.13..993.288..4109..30207..69126..478889..4890117..30295907..239161610
.21.2867.598.13836.124598.260517.2630794.30295907.181435839.1835718615
LINKS
FORMULA
Empirical for column k:
k=1: a(n) = a(n-1) +a(n-2)
k=2: a(n) = a(n-1) +3*a(n-2) +8*a(n-3) -4*a(n-4) -16*a(n-5) for n>6
k=3: [order 15] for n>18
k=4: [order 57] for n>60
EXAMPLE
Some solutions for n=5 k=4
..0..0..1..0. .0..1..0..1. .0..1..1..0. .0..0..1..0. .0..0..0..1
..1..0..0..1. .0..0..1..1. .0..1..1..0. .1..0..0..1. .1..0..0..1
..0..0..0..0. .0..1..1..1. .0..0..0..0. .0..0..0..0. .0..0..0..0
..1..0..0..1. .0..1..1..0. .0..0..0..0. .1..0..0..1. .1..0..0..1
..0..0..0..1. .1..1..1..1. .0..1..1..0. .1..0..0..0. .0..1..0..0
CROSSREFS
Column 1 is A000045(n-1).
Sequence in context: A116854 A331692 A016567 * A305452 A304704 A316455
KEYWORD
nonn,tabl
AUTHOR
R. H. Hardin, May 05 2018
STATUS
approved