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A160953 Sum_{d|n} Moebius(n/d)*d^(b-1)/phi(n) for b = 10. 2
1, 511, 9841, 130816, 488281, 5028751, 6725601, 33488896, 64566801, 249511591, 235794769, 1287360256, 883708281, 3436782111, 4805173321, 8573157376, 7411742281, 32993635311, 17927094321, 63874967296, 66186639441 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

REFERENCES

J. H. Kwak and J. Lee, Enumeration of graph coverings, surface branched coverings and related group theory, in Combinatorial and Computational Mathematics (Pohang, 2000), ed. S. Hong et al., World Scientific, Singapore 2001, pp. 97-161. See p. 134.

LINKS

Enrique Pérez Herrero, Table of n, a(n) for n = 1..5000

Enrique Pérez Herrero, Mathematica Package: Jordan Totient Function.

FORMULA

a(n)=J_9(n)/phi(n)=A069094(n)/A000010(n)

MATHEMATICA

JordanTotient[n_, k_:1]:=DivisorSum[n, #^k*MoebiusMu[n/#]&]/; (n>0)&&IntegerQ[n];

A160953[n_]:=JordanTotient[n, 9]/JordanTotient[n];

CROSSREFS

Sequence in context: A204739 A075948 A011559 * A038996 A068025 A075943

Adjacent sequences:  A160950 A160951 A160952 * A160954 A160955 A160956

KEYWORD

nonn,mult

AUTHOR

N. J. A. Sloane, Nov 19 2009

EXTENSIONS

Definition corrected by Enrique Pérez Herrero, Oct 30 2010

STATUS

approved

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Last modified November 23 17:19 EST 2014. Contains 249851 sequences.