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A183913
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Number of nondecreasing arrangements of n numbers in -5..5 with sum zero
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2
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1, 6, 18, 55, 141, 338, 734, 1514, 2934, 5448, 9686, 16660, 27718, 44916, 70922, 109583, 165821, 246448, 360002, 517971, 734517, 1028172, 1421530, 1943488, 2628824, 3521260, 4672836, 6147894, 8022362, 10388788, 13355414, 17052653
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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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FORMULA
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Empirical: a(n)=a(n-1)+2*a(n-2)-a(n-3)-a(n-4)-a(n-5)+a(n-9)-a(n-10)+3*a(n-12)+a(n-13)-a(n-14)-a(n-16)-2*a(n-17)-a(n-18)-a(n-20)+a(n-22)+2*a(n-23)+2*a(n-24)+a(n-25)-a(n-27)-a(n-29)-2*a(n-30)-a(n-31)-a(n-33)+a(n-34)+3*a(n-35)-a(n-37)+a(n-38)-a(n-42)-a(n-43)-a(n-44)+2*a(n-45)+a(n-46)-a(n-47)
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EXAMPLE
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Some solutions for n=4
.-5...-4...-4...-5...-4...-4...-3...-4...-4...-2...-3...-5...-3...-1...-3...-3
.-1...-1...-2....0...-4....0...-3...-2....1...-1...-1...-2....0....0...-2...-1
..2....1....1....0....3....1....1....2....1...-1...-1....2....1....0....0....1
..4....4....5....5....5....3....5....4....2....4....5....5....2....1....5....3
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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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