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A250795
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Number of (n+1) X (6+1) 0..1 arrays with nondecreasing min(x(i,j), x(i,j-1)) in the i direction and nondecreasing absolute value of x(i,j)-x(i-1,j) in the j direction.
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1
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530, 1818, 6230, 21610, 76110, 270598, 968942, 3485538, 12580830, 45517150, 164970110, 598685226, 2174802030, 7906183238, 28758522030, 104655742642, 380990823486, 1387358367918, 5053131325982, 18408177907066, 67069331582158
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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) = 12*a(n-1) -49*a(n-2) +50*a(n-3) +165*a(n-4) -408*a(n-5) +a(n-6) +618*a(n-7) -224*a(n-8) -344*a(n-9) +108*a(n-10) +72*a(n-11).
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EXAMPLE
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Some solutions for n=4
..1..1..1..1..0..0..1....1..0..0..1..0..0..1....1..0..0..0..1..0..1
..1..1..1..1..0..1..0....1..0..0..1..0..1..0....0..1..1..1..0..1..0
..1..1..1..1..0..0..1....1..0..0..0..1..0..1....0..1..1..1..1..0..1
..1..1..1..1..0..1..0....1..0..0..1..0..1..0....0..1..1..1..1..0..0
..1..1..1..1..0..1..1....1..0..0..1..0..1..1....0..1..1..1..1..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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