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A048785
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tau(n^3), where tau = number of divisors (A000005).
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9
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0, 1, 4, 4, 7, 4, 16, 4, 10, 7, 16, 4, 28, 4, 16, 16, 13, 4, 28, 4, 28, 16, 16, 4, 40, 7, 16, 10, 28, 4, 64, 4, 16, 16, 16, 16, 49, 4, 16, 16, 40, 4, 64, 4, 28, 28, 16, 4, 52, 7, 28, 16, 28, 4, 40, 16, 40, 16, 16, 4, 112, 4, 16, 28, 19, 16, 64, 4, 28, 16
(list; graph; refs; listen; history; internal format)
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OFFSET
| 0,3
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COMMENTS
| a(n)=sum(d|n, 3^omega(d)) where omega(x) is the number of distinct prime factors in factorization of x. - Benoit Cloitre (benoit7848c(AT)orange.fr), Apr 14 2002
Multiplicative with a(p^e) = 3e+1. Mitch Harris (Harris.Mitchell(AT)mgh.harvard.edu) Jun 09, 2005.
The inverse Mobius transform of A074816. - R. J. Mathar, Feb 09 2011
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REFERENCES
| David Johnson-Davies (david(AT)interface.co.uk)
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CROSSREFS
| Sequence in context: A204156 A163106 A146564 * A204008 A016711 A023404
Adjacent sequences: A048782 A048783 A048784 * A048786 A048787 A048788
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KEYWORD
| nonn,mult
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AUTHOR
| N. J. A. Sloane (njas(AT)research.att.com).
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