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A108775
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Floor(sigma(n)/n).
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0
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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
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,6
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COMMENTS
| The sequence is unbounded. - Vrabec
First occurrence of k: 1,6,120,27720,..., which is A023199. - Robert G. Wilson v (rgwv(AT)rgwv.com), Jun 28 2005
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
| W. Sierpinski, Elementary Theory of Numbers, 1987, p. 174 ff.
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EXAMPLE
| a(6) = 2 because sigma(6)/6 = (1+2+3+6)/6 = 2
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MATHEMATICA
| Table[ Floor[ DivisorSigma[1, n]/n], {n, 105}] (* from Robert G. Wilson v (rgwv(AT)rgwv.com), Jun 28 2005 *)
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CROSSREFS
| Cf. A000203, A054024.
Sequence in context: A204897 A107577 A073700 * A074971 A198067 A132587
Adjacent sequences: A108772 A108773 A108774 * A108776 A108777 A108778
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KEYWORD
| nonn,changed
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AUTHOR
| Franz Vrabec (franz.vrabec(AT)aon.at), Jun 27 2005
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EXTENSIONS
| More terms from Robert G. Wilson v (rgwv(AT)rgwv.com), Jun 28 2005
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