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A189491
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Number of arrangements of n+1 nonzero numbers x(i) in -2..2 with the sum of floor(x(i)/x(i+1)) equal to zero
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1
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2, 12, 42, 136, 550, 1892, 7384, 26816, 103288, 386928, 1485566, 5654000, 21736466, 83448592, 321767288, 1241835856, 4803432344, 18605438864, 72168550344, 280295950240, 1089835505354, 4242072071396, 16526909026016, 64446293812896
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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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EXAMPLE
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Some solutions for n=5
..1....2....2....2....1...-2....1...-1....1....2...-1....1...-1....1....1...-1
..2....1...-2...-1...-2...-1...-2...-2....1....2...-1...-2....1....2...-2....2
..2....1...-1...-2...-2....2....2...-1...-1...-1...-2....1....1...-2...-2...-2
.-2...-1....2...-1....2....2....1....1....2...-1....2....2...-2....2....1...-1
.-2....1....2...-1...-2...-2...-1....2....1....2...-2....2...-1....1....1....1
..2...-1...-2....2...-1....2...-1...-2...-2....2...-2....1....1....2....1....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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