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A066851
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Number of ordered solutions (x,y,z) to xy + yz + zx = n with x,y,z >= 1.
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2
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0, 0, 1, 0, 3, 0, 3, 3, 3, 0, 9, 1, 3, 6, 6, 3, 9, 0, 9, 9, 6, 0, 15, 6, 3, 12, 10, 3, 15, 0, 15, 12, 6, 6, 18, 9, 3, 12, 18, 6, 21, 0, 9, 21, 9, 6, 27, 7, 9, 12, 18, 9, 15, 12, 18, 24, 6, 0, 33, 6, 15, 18, 21, 12, 18, 12, 9, 27, 18, 0, 39, 9, 9, 24, 19, 21, 18, 0, 27, 27, 18, 6, 33, 18, 6
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OFFSET
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1,5
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LINKS
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EXAMPLE
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a(5) = 3 since there are solutions (2,1,1), (1,2,1), (1,1,2).
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CROSSREFS
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KEYWORD
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easy,nonn
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AUTHOR
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Colin Mallows, Jan 24 2002
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EXTENSIONS
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STATUS
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approved
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