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A200206
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Number of -n..n arrays x(0..4) of 5 elements with zero sum and nonzero second and third differences
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1
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22, 246, 1106, 3196, 7450, 14842, 26932, 44910, 71050, 106802, 155056, 217506, 297896, 397820, 522032, 672214, 853824, 1068640, 1323238, 1619004, 1963760, 2358796, 2812794, 3326992, 3911394, 4566542, 5303990, 6124024, 7039122, 8049358
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OFFSET
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1,1
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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) +a(n-3) -a(n-5) +a(n-6) -2*a(n-7) +2*a(n-8) -2*a(n-9) +2*a(n-13) -2*a(n-14) +2*a(n-15) -a(n-16) +a(n-17) -a(n-19) -a(n-21) +a(n-22)
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EXAMPLE
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Some solutions for n=3
..3....0...-2...-3...-3....0...-1....1....3....0....3....2....0....0...-1....0
..2...-3....1...-3....3....3...-1....2...-3....1....1....1....2....0...-1...-2
.-1....3....1....3....2...-2....2...-3....2....0...-3...-2...-1...-3....3....1
.-3...-2....3....0...-1...-3....1....3...-2...-2....1...-3...-3....2....0....3
.-1....2...-3....3...-1....2...-1...-3....0....1...-2....2....2....1...-1...-2
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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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