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A061194
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Minimum positive value of lcm{1,...,n}*(s_1/1 + ... + s_n/n), where each s_i equals 1 or -1.
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2
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1, 1, 1, 1, 7, 3, 11, 13, 11, 11, 23, 23, 607, 251, 251, 125, 97, 97, 3767, 3767, 3767, 2285, 24319, 24319, 71559, 4261, 13703, 13703, 872843, 872843, 17424097, 13828799, 902339, 7850449, 7850449, 7850449, 10683197, 68185267, 37728713, 37728713, 740674333
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OFFSET
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1,5
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COMMENTS
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Nonnegative by considering the largest power of 2 up to n.
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LINKS
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EXAMPLE
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1/1 - 1/2 - 1/3 - 1/4 - 1/5 + 1/6 + 1/7 = 11/420 = 11/lcm(1,2,3,4,5,6,7), so a(7) <= 11; no other choice of signs yields 1/420, ..., 10/420, so a(7)=11.
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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Greg Martin (gerg(AT)math.toronto.edu), Apr 19 2001
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EXTENSIONS
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STATUS
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approved
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