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A250448
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Number of (n+1)X(2+1) 0..2 arrays with nondecreasing min(x(i,j),x(i,j-1)) in the i direction and nondecreasing min(x(i,j),x(i-1,j)) in the j direction
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1
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217, 2029, 17024, 141857, 1155519, 9376751, 75647740, 609534839, 4903892459, 39438538201, 317050695780, 2548528796645, 20483568025431, 164629748544475, 1323120367104228, 10633755035857083, 85461577059693963, 686837682555429189
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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) = 10*a(n-1) +6*a(n-2) -210*a(n-3) +173*a(n-4) +976*a(n-5) -674*a(n-6) -1632*a(n-7) +800*a(n-8) +1128*a(n-9) -288*a(n-10) -288*a(n-11)
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EXAMPLE
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Some solutions for n=4
..0..2..0....0..0..0....0..1..0....0..1..0....0..2..0....1..0..1....0..0..2
..0..0..1....0..0..0....1..0..2....1..0..0....2..0..2....0..0..2....2..0..0
..1..0..0....0..0..0....0..0..1....0..1..0....0..1..1....1..0..2....0..0..1
..0..1..2....1..0..2....1..0..1....2..0..0....2..1..2....0..0..2....0..0..2
..2..2..1....0..2..1....0..1..1....0..0..0....1..2..2....1..1..1....0..0..2
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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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