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A297085
T(n,k)=Number of nXk 0..1 arrays with no 1 adjacent to 2 king-move neighboring 1s.
8
2, 4, 4, 7, 12, 7, 13, 30, 30, 13, 24, 96, 136, 96, 24, 44, 286, 687, 687, 286, 44, 81, 848, 3616, 6784, 3616, 848, 81, 149, 2620, 19277, 64819, 64819, 19277, 2620, 149, 274, 7964, 105494, 654120, 1180260, 654120, 105494, 7964, 274, 504, 24332, 581688
OFFSET
1,1
COMMENTS
Table starts
...2.....4.......7........13...........24.............44................81
...4....12......30........96..........286............848..............2620
...7....30.....136.......687.........3616..........19277............105494
..13....96.....687......6784........64819.........654120...........6743851
..24...286....3616.....64819......1180260.......22630723.........444282892
..44...848...19277....654120.....22630723......833228038.......31284950414
..81..2620..105494...6743851....444282892....31284950414.....2245841563645
.149..7964..581688..69857453...8764056739..1180379285603...161959380452328
.274.24332.3225186.727765313.173651084724.44714930487805.11725115199949679
LINKS
FORMULA
Empirical for column k:
k=1: a(n) = a(n-1) +a(n-2) +a(n-3)
k=2: a(n) = 2*a(n-1) +4*a(n-2) +4*a(n-3) -14*a(n-4) -14*a(n-5) -4*a(n-6)
k=3: [order 17]
k=4: [order 34]
EXAMPLE
Some solutions for n=5 k=4
..1..1..0..0. .0..0..0..1. .0..1..0..1. .0..0..1..0. .0..0..0..0
..1..1..0..1. .0..0..0..1. .1..0..0..0. .1..1..1..1. .0..0..0..1
..0..1..1..0. .0..0..0..0. .0..0..0..0. .0..0..1..1. .1..0..0..0
..1..0..0..0. .0..0..0..0. .0..0..0..1. .0..1..1..1. .0..0..0..0
..0..0..1..1. .0..0..1..1. .1..0..1..0. .1..0..1..1. .0..1..1..0
CROSSREFS
Column 1 is A000073(n+3).
Sequence in context: A225900 A227558 A296651 * A224158 A224409 A226870
KEYWORD
nonn,tabl
AUTHOR
R. H. Hardin, Dec 25 2017
STATUS
approved