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A188176
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Number of strictly increasing arrangements of n numbers in -(n+2)..(n+2) with sum zero
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1
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1, 4, 13, 43, 141, 480, 1656, 5744, 20094, 70922, 252117, 901723, 3243531, 11728606, 42611990, 155484150, 569585274, 2094177794, 7725489976, 28588154238, 106095329440, 394792407478, 1472734812454, 5506709078310, 20635115495666
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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=5
.-4...-5...-7...-5...-7...-6...-5...-3...-6...-6...-6...-4...-7...-7...-5...-6
.-3...-1...-2...-3...-5...-5...-4...-2...-4...-2...-3...-3...-2...-4...-4...-4
.-2....0....1...-2...-1....1...-1....0...-1....0...-1...-1....0....0...-3....2
..2....1....2....4....6....3....3....2....5....3....3....3....3....4....5....3
..7....5....6....6....7....7....7....3....6....5....7....5....6....7....7....5
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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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