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A251024
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Number of (n+1)X(4+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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6321, 23404, 51347, 119632, 257578, 563271, 1199576, 2590598, 5601754, 12305560, 27283810, 61222845, 138410707, 315015070, 719847225, 1649954072, 3788495903, 8709393619, 20035602376, 46111319584, 106149006168, 244393023772
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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>14
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EXAMPLE
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Some solutions for n=4
..0..0..1..2..3....0..0..0..1..0....0..0..0..0..2....0..2..2..2..3
..0..0..0..0..1....2..0..0..1..0....0..0..0..0..2....1..0..0..0..1
..2..2..2..2..2....2..0..0..1..0....0..0..0..0..2....1..0..0..0..1
..0..0..0..0..0....2..0..0..1..0....0..0..0..0..2....1..0..0..0..1
..3..3..3..3..1....3..1..1..1..0....2..2..1..1..1....2..0..0..0..1
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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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