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A048785 tau(n^3), where tau = number of divisors (A000005). 9
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; text; internal format)
OFFSET

0,3

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, Apr 14 2002

Multiplicative with a(p^e) = 3e+1. Mitch Harris Jun 09, 2005.

The inverse Mobius transform of A074816. - R. J. Mathar, Feb 09 2011

REFERENCES

David Johnson-Davies

LINKS

Table of n, a(n) for n=0..69.

CROSSREFS

Sequence in context: A204156 A163106 A146564 * A204008 A016711 A023404

Adjacent sequences:  A048782 A048783 A048784 * A048786 A048787 A048788

KEYWORD

nonn,mult

AUTHOR

N. J. A. Sloane.

STATUS

approved

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Last modified May 19 22:13 EDT 2013. Contains 225436 sequences.