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A231586
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T(n,k)=Number of nXk 0..3 arrays with no element less than a strict majority of its horizontal, vertical, diagonal and antidiagonal neighbors
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6
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4, 4, 4, 16, 28, 16, 50, 124, 124, 50, 144, 602, 2352, 602, 144, 422, 2776, 32650, 32650, 2776, 422, 1268, 12922, 381076, 1245468, 381076, 12922, 1268, 3823, 60720, 5618444, 38768838, 38768838, 5618444, 60720, 3823, 11472, 286047, 82479418, 1453028265
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OFFSET
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1,1
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COMMENTS
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Table starts
.....4.......4...........16...............50................144
.....4......28..........124..............602...............2776
....16.....124.........2352............32650.............381076
....50.....602........32650..........1245468...........38768838
...144....2776.......381076.........38768838.........2912579313
...422...12922......5618444.......1453028265.......260228939106
..1268...60720.....82479418......57099276134.....24813120747919
..3823..286047...1142396851....2144257250786...2275463989704521
.11472.1335296..16061107556...79701582158514.205616812796559119
.34350.6256326.231334122108.3015862229160377
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LINKS
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FORMULA
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Empirical for column k:
k=1: a(n) = 4*a(n-1) -6*a(n-2) +10*a(n-3) -5*a(n-4) +6*a(n-5) -a(n-6) +a(n-7) for n>8
k=2: [order 16]
k=3: [order 72] for n>73
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EXAMPLE
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Some solutions for n=3 k=4
..3..2..1..1....2..0..0..0....1..1..1..3....0..0..1..2....0..3..0..0
..2..1..1..1....0..0..0..1....1..1..1..2....2..0..0..2....0..0..0..2
..2..1..1..2....2..0..0..2....1..1..2..2....3..3..0..0....2..0..0..3
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CROSSREFS
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KEYWORD
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AUTHOR
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STATUS
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approved
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