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A230989
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T(n,k)=Number of white square subarrays of (n+1)X(k+1) binary arrays with no element equal to a strict majority of its diagonal and antidiagonal neighbors, with upper left element zero
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8
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1, 1, 1, 2, 1, 2, 3, 4, 4, 3, 5, 5, 11, 5, 5, 8, 15, 24, 24, 15, 8, 13, 20, 59, 47, 59, 20, 13, 21, 57, 139, 191, 191, 139, 57, 21, 34, 77, 332, 396, 685, 396, 332, 77, 34, 55, 218, 796, 1573, 2379, 2379, 1573, 796, 218, 55, 89, 295, 1903, 3317, 8357, 7357, 8357, 3317
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OFFSET
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1,4
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COMMENTS
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Table starts
..1..1...2....3.....5......8......13......21.......34........55.........89
..1..1...4....5....15.....20......57......77......218.......295........835
..2..4..11...24....59....139.....332.....796.....1903......4563......10934
..3..5..24...47...191....396....1573....3317....13176.....27805.....110739
..5.15..59..191...685...2379....8357...29493...103842....366761....1295168
..8.20.139..396..2379...7357...43004..135154...793041...2491365...14671984
.13.57.332.1573..8357..43004..223270.1168723..6098749..31928221..167211867
.21.77.796.3317.29493.135154.1168723.5447557.47403200.220834521.1930022303
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LINKS
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FORMULA
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Empirical for column k:
k=1: a(n) = a(n-1) +a(n-2)
k=2: a(n) = 5*a(n-2) -5*a(n-4) +2*a(n-6)
k=3: a(n) = 2*a(n-1) +3*a(n-2) -3*a(n-3) -6*a(n-4) +2*a(n-5) +4*a(n-6) -a(n-7) -a(n-8)
k=4: [order 18, even terms]
k=5: [order 32]
k=6: [order 70, even terms]
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EXAMPLE
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Some solutions for n=6 k=4
..0..x..0..x..1....0..x..0..x..1....0..x..0..x..0....0..x..0..x..0
..x..1..x..0..x....x..1..x..0..x....x..1..x..1..x....x..1..x..1..x
..1..x..0..x..1....0..x..1..x..1....0..x..0..x..1....1..x..0..x..1
..x..0..x..1..x....x..0..x..1..x....x..1..x..0..x....x..0..x..0..x
..1..x..1..x..0....1..x..0..x..0....0..x..1..x..0....1..x..1..x..1
..x..0..x..0..x....x..0..x..1..x....x..0..x..1..x....x..0..x..0..x
..1..x..1..x..1....1..x..1..x..0....1..x..0..x..0....1..x..1..x..1
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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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