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A202505
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Number of zero-sum -2..2 arrays of n elements with first through third differences also in -2..2
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1
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1, 3, 5, 15, 21, 53, 109, 239, 489, 1051, 2253, 4853, 10511, 23033, 50791, 112187, 248217, 549917, 1220585, 2712351, 6037825, 13459637, 30045375, 67137267, 150165265, 336151499, 753099801, 1688448381, 3788174371, 8504582261
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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=7
..0...-1....1....2....0...-1...-2...-1...-2....0....2....2....2....1...-2....0
..1....0....0....0...-1...-2...-2....0...-1...-1....0....0....1....1...-2....0
..2....1....0...-2...-1...-1...-2....1...-1....0...-1...-1....1....0....0....0
..1....1....0...-2....0....0....0....2....0....1...-1....0....0....0....2....0
.-1....1...-1...-1....0....1....2....1....1....1....0....1...-1....0....2....0
.-2....0...-1....1....1....1....2...-1....2....0....0....0...-1....0....1....0
.-1...-2....1....2....1....2....2...-2....1...-1....0...-2...-2...-2...-1....0
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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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