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A225986
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Number of pairs of orthogonal (-x,y) vectors of length 1*(x+y), where x/y is the n-th rational <= 1, ordered first by y and then x, e.g. 1/1, 1/2, 1/3, 2/3, 1/4, 3/4 ...
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1
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4, 9, 20, 60, 45, 420, 102, 378, 1120, 3024, 231, 22176, 520, 2376, 8160, 23760, 63360, 164736, 1161, 21780, 185328, 1235520, 2570, 14190, 188760, 544544, 3660800, 9335040, 5643, 147576, 11202048, 70946304, 12300, 80028, 374192, 1408680
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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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All solutions for n=1
.-1..1...-1.-1...-1..1....1..1
.-1.-1...-1..1....1..1...-1..1
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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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