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A231544
T(n,k)=Number of nXk 0..1 arrays with no element less than a strict majority of its horizontal, vertical and antidiagonal neighbors
8
2, 2, 2, 4, 6, 4, 7, 20, 20, 7, 12, 57, 116, 57, 12, 21, 164, 589, 589, 164, 21, 37, 485, 3001, 5235, 3001, 485, 37, 65, 1424, 15644, 46122, 46122, 15644, 1424, 65, 114, 4169, 81179, 417298, 698721, 417298, 81179, 4169, 114, 200, 12228, 420243, 3763223, 10928292
OFFSET
1,1
COMMENTS
Table starts
...2.....2........4..........7...........12..............21................37
...2.....6.......20.........57..........164.............485..............1424
...4....20......116........589.........3001...........15644.............81179
...7....57......589.......5235........46122..........417298...........3763223
..12...164.....3001......46122.......698721........10928292.........170393737
..21...485....15644.....417298.....10928292.......296647240........8028429092
..37..1424....81179....3763223....170393737......8028429092......377320795091
..65..4169...420243...33812753...2643967833....216093538039....17623244476340
.114.12228..2177937..304137386..41079980720...5824887373442...824325064919737
.200.35868.11287977.2736503160.638622184605.157116139854017.38588079925163243
LINKS
FORMULA
Empirical for column k:
k=1: a(n) = 2*a(n-1) -a(n-2) +a(n-3) for n>4
k=2: a(n) = 4*a(n-1) -4*a(n-2) +5*a(n-3) -8*a(n-4) +3*a(n-5) -2*a(n-6) +a(n-7) -a(n-8)
k=3: [order 22]
k=4: [order 61]
EXAMPLE
Some solutions for n=4 k=4
..1..1..1..0....1..1..0..0....1..0..0..0....0..0..1..1....0..0..0..0
..0..0..0..0....1..0..0..0....1..0..1..0....1..0..0..0....0..0..1..0
..0..0..1..1....0..0..0..0....0..1..1..0....0..0..1..0....0..1..0..0
..1..0..0..0....0..0..0..0....0..0..0..1....0..0..0..0....0..0..1..0
CROSSREFS
Column 1 is A005251(n+2)
Sequence in context: A240433 A217637 A231515 * A086420 A328106 A342336
KEYWORD
nonn,tabl
AUTHOR
R. H. Hardin, Nov 10 2013
STATUS
approved