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A304347
T(n,k)=Number of nXk 0..1 arrays with every element unequal to 0, 1, 2, 4 or 5 king-move adjacent elements, with upper left element zero.
8
1, 2, 2, 4, 4, 4, 8, 14, 14, 8, 16, 28, 27, 28, 16, 32, 94, 71, 71, 94, 32, 64, 284, 225, 290, 225, 284, 64, 128, 752, 613, 1266, 1266, 613, 752, 128, 256, 2244, 1752, 4733, 6373, 4733, 1752, 2244, 256, 512, 6532, 5102, 18855, 27505, 27505, 18855, 5102, 6532, 512
OFFSET
1,2
COMMENTS
Table starts
...1....2.....4......8......16.......32........64........128.........256
...2....4....14.....28......94......284.......752.......2244........6532
...4...14....27.....71.....225......613......1752.......5102.......14673
...8...28....71....290....1266.....4733.....18855......76887......308978
..16...94...225...1266....6373....27505....127511.....633229.....3052998
..32..284...613...4733...27505...135445....741942....4355191....24554331
..64..752..1752..18855..127511...741942...4921043...36193582...250785575
.128.2244..5102..76887..633229..4355191..36193582..343449680..2937754820
.256.6532.14673.308978.3052998.24554331.250785575.2937754820.30008468246
LINKS
FORMULA
Empirical for column k:
k=1: a(n) = 2*a(n-1)
k=2: a(n) = 2*a(n-1) +2*a(n-2) +6*a(n-3) -10*a(n-4) -8*a(n-5) for n>6
k=3: [order 15] for n>16
k=4: [order 57] for n>60
EXAMPLE
Some solutions for n=5 k=4
..0..0..1..0. .0..0..0..0. .0..0..1..1. .0..0..1..1. .0..1..0..1
..1..0..0..1. .1..0..1..1. .0..0..1..1. .0..1..0..1. .0..0..1..1
..0..0..0..0. .0..1..1..1. .1..1..1..1. .1..0..1..0. .1..0..1..0
..1..0..0..1. .1..1..1..0. .0..0..0..0. .0..0..1..1. .0..1..0..1
..1..0..0..0. .1..1..1..0. .1..1..0..0. .0..1..0..1. .0..0..1..1
CROSSREFS
Column 1 is A000079(n-1).
Sequence in context: A317238 A260038 A193916 * A316218 A305642 A317036
KEYWORD
nonn,tabl
AUTHOR
R. H. Hardin, May 11 2018
STATUS
approved