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A296039
T(n,k)=Number of nXk 0..1 arrays with each 1 adjacent to 2 or 4 king-move neighboring 1s.
8
1, 1, 1, 1, 5, 1, 1, 11, 11, 1, 1, 21, 31, 21, 1, 1, 55, 70, 70, 55, 1, 1, 125, 251, 204, 251, 125, 1, 1, 271, 799, 997, 997, 799, 271, 1, 1, 645, 2266, 4102, 8472, 4102, 2266, 645, 1, 1, 1479, 7005, 15399, 51941, 51941, 15399, 7005, 1479, 1, 1, 3325, 21780, 63267
OFFSET
1,5
COMMENTS
Table starts
.1....1.....1......1........1.........1..........1............1.............1
.1....5....11.....21.......55.......125........271..........645..........1479
.1...11....31.....70......251.......799.......2266.........7005.........21780
.1...21....70....204......997......4102......15399........63267........258493
.1...55...251....997.....8472.....51941.....285366......1853852......11570787
.1..125...799...4102....51941....472540....3650122.....33758793.....307234618
.1..271..2266..15399...285366...3650122...39608385....518787061....6686146382
.1..645..7005..63267..1853852..33758793..518787061..10042412853..188033223758
.1.1479.21780.258493.11570787.307234618.6686146382.188033223758.5131681923323
LINKS
FORMULA
Empirical for column k:
k=1: a(n) = a(n-1)
k=2: a(n) = a(n-1) +6*a(n-3) +4*a(n-5)
k=3: [order 11]
k=4: [order 17]
k=5: [order 55]
EXAMPLE
Some solutions for n=5 k=4
..1..1..0..0. .0..0..1..1. .0..0..1..1. .0..1..1..0. .0..0..1..0
..1..0..0..0. .0..0..0..1. .0..0..0..1. .0..0..1..0. .0..1..0..1
..0..0..0..0. .0..0..0..0. .0..0..0..0. .0..0..0..0. .0..0..1..0
..0..0..1..1. .0..0..0..1. .1..1..0..0. .0..1..1..1. .0..1..0..1
..0..0..0..1. .0..0..1..1. .1..0..0..0. .0..1..0..1. .0..0..1..0
CROSSREFS
Sequence in context: A132787 A181370 A119307 * A296974 A146954 A174949
KEYWORD
nonn,tabl
AUTHOR
R. H. Hardin, Dec 03 2017
STATUS
approved