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A200055
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Number of -6..6 arrays x(0..n-1) of n elements with zero sum and elements alternately strictly increasing and strictly decreasing
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1
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1, 12, 78, 546, 3914, 28554, 211242, 1577878, 11867186, 89815404, 682642050, 5211283212, 39897460856, 306446600454, 2358644800468, 18199380449274, 140644480480176, 1089068472750998, 8443172123261506, 65564035662489652
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OFFSET
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1,2
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COMMENTS
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LINKS
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EXAMPLE
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Some solutions for n=6
.-2....0...-3...-1...-3....5...-2....5....2....1...-3....0....4...-6...-1...-5
..4....5...-5...-2....1...-3....5...-5....1....0....0...-1...-3....3....0....1
.-5...-3....4....1...-6....1...-6....2....5....1...-1....1....1...-4...-2...-6
..4...-2....2...-3....6...-1....5...-2...-6...-3....2...-2...-6....3....5....3
.-5...-4....5....6....0....1...-4....1....1....4...-3....3....6....1...-2....1
..4....4...-3...-1....2...-3....2...-1...-3...-3....5...-1...-2....3....0....6
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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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