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A108775
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a(n) = floor(sigma(n)/n).
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7
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1, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 2, 1, 2, 1, 1, 1, 2, 1, 1, 1, 2, 1, 2, 1, 1, 1, 1, 1, 2, 1, 1, 1, 2, 1, 2, 1, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 2, 1, 2, 1, 1, 1, 2, 1, 1, 1, 1, 1, 2, 1, 1, 1, 2, 1, 2, 1, 1, 1, 1, 1, 2, 1, 2, 1, 1, 1, 2, 1, 1, 1, 2, 1, 2, 1, 1, 1, 1, 1, 2, 1, 1, 1, 2, 1, 2, 1, 2, 1
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OFFSET
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1,6
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COMMENTS
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The sequence is unbounded. - Vrabec
a(n) > 1 if n is perfect or abundant. a(n) = 2 if n is perfect or primitive abundant (see A091191). - Alonso del Arte, Feb 06 2012
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REFERENCES
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W. Sierpinski, Elementary Theory of Numbers, 1987, p. 174 ff.
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LINKS
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FORMULA
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EXAMPLE
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a(6) = 2 because sigma(6)/6 = (1 + 2 + 3 + 6)/6 = 2.
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MATHEMATICA
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PROG
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(Haskell)
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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