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A199826
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Number of -2..2 arrays x(0..n+1) of n+2 elements with zero sum and no two neighbors summing to zero
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1
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10, 40, 114, 426, 1650, 6126, 23206, 88636, 337866, 1295566, 4992364, 19269156, 74529210, 288954786, 1122363984, 4366362420, 17011617426, 66365823648, 259213619826, 1013542247970, 3966939195402, 15540399135516, 60929935280508
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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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EXAMPLE
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Some solutions for n=3
..0....0...-1....0...-1....1...-1...-1....1....1...-1...-2....0...-2....1....1
..1...-1...-2...-2....2....2....0...-2....0....2...-2....1....2...-2....1...-2
.-2...-1....0....0....0....1...-1....1....1....0....1....0...-1....1....0...-1
..1....2....2....2....1...-2....2....1...-2...-1....2....2...-1....2...-2....2
..0....0....1....0...-2...-2....0....1....0...-2....0...-1....0....1....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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