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A188116
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Number of strictly increasing arrangements of n nonzero numbers in -(n+1)..(n+1) with sum zero
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2
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0, 3, 4, 16, 42, 137, 426, 1398, 4622, 15594, 53252, 184060, 642392, 2261829, 8024726, 28664946, 103015222, 372234190, 1351655526, 4930080182, 18055480464, 66371559466, 244817099870, 905883648170, 3361795172242, 12509691344838
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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
.-4...-5...-7...-7...-7...-5...-7...-7...-7...-7...-6...-7...-5...-5...-7...-6
.-3...-3...-6...-5...-5...-4...-3...-4...-6...-4...-5...-6...-3...-2...-6...-4
.-2...-2...-1...-2....1...-3....1...-2....1...-2...-4...-2...-2...-1...-1...-2
..2...-1....3....2....2....3....2....3....3....2....2....3...-1....1....2....1
..3....5....5....5....4....4....3....4....4....4....6....5....4....3....5....5
..4....6....6....7....5....5....4....6....5....7....7....7....7....4....7....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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