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A303888
T(n,k)=Number of nXk 0..1 arrays with every element unequal to 0, 2, 3 or 4 king-move adjacent elements, with upper left element zero.
8
1, 1, 1, 1, 4, 1, 1, 8, 8, 1, 1, 24, 11, 24, 1, 1, 82, 36, 36, 82, 1, 1, 272, 87, 166, 87, 272, 1, 1, 908, 256, 487, 487, 256, 908, 1, 1, 3076, 684, 2130, 1150, 2130, 684, 3076, 1, 1, 10444, 1932, 7433, 4964, 4964, 7433, 1932, 10444, 1, 1, 35480, 5308, 30191, 16431
OFFSET
1,5
COMMENTS
Table starts
.1.....1....1......1......1.......1.......1........1.........1.........1
.1.....4....8.....24.....82.....272.....908.....3076.....10444.....35480
.1.....8...11.....36.....87.....256.....684.....1932......5308.....14809
.1....24...36....166....487....2130....7433....30191....112815....444834
.1....82...87....487...1150....4964...16431....68704....254498...1032541
.1...272..256...2130...4964...24985...88901...384168...1517262...6387363
.1...908..684...7433..16431...88901..308271..1437397...5832957..25738579
.1..3076.1932..30191..68704..384168.1437397..7577931..32153502.162027971
.1.10444.5308.112815.254498.1517262.5832957.32153502.148783767.818391800
LINKS
FORMULA
Empirical for column k:
k=1: a(n) = a(n-1)
k=2: a(n) = 4*a(n-1) -2*a(n-2) +2*a(n-3) -6*a(n-4) -4*a(n-5) for n>6
k=3: [order 16] for n>18
k=4: [order 38] for n>41
EXAMPLE
Some solutions for n=5 k=4
..0..1..1..1. .0..1..1..0. .0..1..1..0. .0..1..0..1. .0..1..1..0
..0..1..1..1. .0..1..1..0. .1..0..0..1. .1..0..0..1. .1..0..0..1
..1..1..1..1. .0..1..1..1. .1..0..0..1. .1..0..0..1. .0..0..0..1
..0..1..1..1. .1..1..1..0. .0..0..0..0. .1..0..0..1. .1..0..0..1
..1..0..0..0. .0..0..1..0. .1..1..0..1. .0..1..1..0. .0..1..1..0
CROSSREFS
Sequence in context: A332307 A296405 A174035 * A305281 A304894 A316576
KEYWORD
nonn,tabl
AUTHOR
R. H. Hardin, May 02 2018
STATUS
approved