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A211691
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Number of -4..4 arrays x(i) of n+1 elements i=1..n+1 with x(i)+x(j), x(i+1)+x(j+1), -(x(i)+x(j+1)), and -(x(i+1)+x(j)) having three or four distinct values for every i<=n and j<=n
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1
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68, 516, 3848, 28464, 208560, 1516160, 10941536, 78444752, 559061552, 3962850688, 27952463280, 196285510848, 1372724453104, 9564449019232, 66413636701040, 459728500804384, 3173268698181920, 21846285064971776, 150040513219495120
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OFFSET
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1,1
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LINKS
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EXAMPLE
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Some solutions for n=5
.-4...-1...-3...-1...-3...-2...-4...-4...-4...-2...-1...-3...-4....0....0...-4
.-2....2...-4....4....3...-1....1....2....1...-4...-2...-1....0...-3...-4....2
..0....3....1...-2....1...-3....0...-3...-2....1...-1....0....2....3...-1....4
..4....4....3....0...-4....0...-4....4....0....0...-4....4...-3...-3....4...-4
..3....1....0...-1....3...-1....0...-2...-3...-4....4...-3...-2....3....1....2
.-4....2....3....4....1....1....2....0....0....1....2....3...-3...-2....0....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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