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A316953
T(n,k)=Number of nXk 0..1 arrays with every element unequal to 1, 2, 3, 4, 5, 6 or 7 king-move adjacent elements, with upper left element zero.
7
0, 1, 1, 1, 7, 1, 2, 25, 25, 2, 3, 98, 160, 98, 3, 5, 383, 1240, 1240, 383, 5, 8, 1493, 9417, 18956, 9417, 1493, 8, 13, 5824, 71505, 287292, 287292, 71505, 5824, 13, 21, 22717, 543155, 4335826, 8641499, 4335826, 543155, 22717, 21, 34, 88609, 4125662
OFFSET
1,5
COMMENTS
Table starts
..0.....1........1...........2.............3................5
..1.....7.......25..........98...........383.............1493
..1....25......160........1240..........9417............71505
..2....98.....1240.......18956........287292..........4335826
..3...383.....9417......287292.......8641499........259163370
..5..1493....71505.....4335826.....259163370......15440641209
..8..5824...543155....65510494....7779344498.....920789559090
.13.22717..4125662...989703110..233495963949...54906173292280
.21.88609.31337363.14951804382.7008276669223.3273992108473660
LINKS
FORMULA
Empirical for column k:
k=1: a(n) = a(n-1) +a(n-2)
k=2: a(n) = 3*a(n-1) +3*a(n-2) +2*a(n-3)
k=3: a(n) = 6*a(n-1) +10*a(n-2) +15*a(n-3) +8*a(n-4) +3*a(n-5) +a(n-6) +2*a(n-7)
k=4: [order 13]
k=5: [order 33]
k=6: [order 76]
EXAMPLE
Some solutions for n=5 k=4
..0..0..0..1. .0..0..0..0. .0..0..1..0. .0..0..0..0. .0..0..1..0
..1..0..1..0. .1..0..0..1. .1..1..1..0. .0..1..1..0. .0..1..1..1
..1..1..0..1. .0..0..1..1. .1..1..0..0. .1..1..1..1. .0..1..1..0
..1..1..0..0. .0..1..0..1. .1..0..0..1. .0..1..0..1. .0..1..0..1
..0..0..1..1. .1..1..1..1. .1..0..1..0. .1..0..0..0. .0..1..1..1
CROSSREFS
Column 1 is A000045(n-1).
Column 2 is A304421.
Sequence in context: A317222 A305692 A317072 * A317733 A258335 A266985
KEYWORD
nonn,tabl
AUTHOR
R. H. Hardin, Jul 17 2018
STATUS
approved