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A305452
T(n,k)=Number of nXk 0..1 arrays with every element unequal to 1, 2, 4, 5 or 8 king-move adjacent elements, with upper left element zero.
7
0, 1, 1, 1, 3, 1, 2, 11, 11, 2, 3, 10, 7, 10, 3, 5, 51, 20, 20, 51, 5, 8, 165, 44, 26, 44, 165, 8, 13, 306, 77, 169, 169, 77, 306, 13, 21, 993, 181, 475, 1275, 475, 181, 993, 21, 34, 2867, 379, 1234, 2697, 2697, 1234, 379, 2867, 34, 55, 6818, 849, 5007, 13128, 5443, 13128
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...7....20.....44.....77.....181......379.......849.......1799
..2...10..20....26....169....475....1234.....5007.....16422......51196
..3...51..44...169...1275...2697...13128....58608....222877.....971263
..5..165..77...475...2697...5443...30344...132479....485885....2234246
..8..306.181..1234..13128..30344..222961..1378090...6504099...42968149
.13..993.379..5007..58608.132479.1378090.10709608..62295992..516604339
.21.2867.849.16422.222877.485885.6504099.62295992.362139243.3817890104
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 17] for n>18
k=4: [order 63] for n>65
EXAMPLE
Some solutions for n=5 k=4
..0..0..1..1. .0..0..1..0. .0..1..0..0. .0..0..1..1. .0..1..1..0
..1..1..1..0. .1..0..0..0. .1..0..0..1. .1..1..1..0. .0..0..0..0
..1..1..1..1. .0..0..0..0. .0..0..0..0. .0..0..0..1. .0..0..0..0
..0..1..1..0. .1..0..0..1. .0..0..0..1. .0..0..1..1. .1..0..0..1
..0..1..1..0. .0..0..1..0. .0..1..0..0. .0..1..0..1. .0..1..0..0
CROSSREFS
Column 1 is A000045(n-1).
Column 2 is A304052.
Sequence in context: A331692 A016567 A304058 * A304704 A316455 A305015
KEYWORD
nonn,tabl
AUTHOR
R. H. Hardin, Jun 01 2018
STATUS
approved