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A251022
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Number of (n+1)X(2+1) 0..3 arrays with no 2X2 subblock having the sum of its diagonal elements greater than the maximum of its antidiagonal elements
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1
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526, 2546, 8207, 23404, 60044, 144737, 334167, 755336, 1690491, 3781186, 8485355, 19144607, 43420578, 98930808, 226191116, 518462850, 1190424308, 2736380757, 6294485365, 14485586642, 33344734931, 76769227278, 176761167633
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OFFSET
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1,1
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COMMENTS
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LINKS
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FORMULA
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Empirical: a(n) = 8*a(n-1) -25*a(n-2) +35*a(n-3) -7*a(n-4) -49*a(n-5) +77*a(n-6) -55*a(n-7) +20*a(n-8) -3*a(n-9) for n>13
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EXAMPLE
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Some solutions for n=4
..0..1..3....0..2..3....0..0..2....0..1..2....0..0..3....1..0..2....1..1..3
..0..0..2....0..0..1....0..0..0....1..1..1....3..3..3....1..0..2....1..0..0
..1..1..1....1..1..1....0..0..0....1..0..0....0..0..0....2..0..2....1..0..0
..0..0..0....0..0..0....1..1..0....2..1..1....2..2..2....2..0..0....1..0..0
..3..0..0....3..3..0....3..1..0....3..1..0....1..0..0....3..0..0....1..0..0
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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