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A160908 Sum_{d|n} Moebius(n/d)*d^(b-1)/phi(n) for b = 9. 5
1, 255, 3280, 32640, 97656, 836400, 960800, 4177920, 7173360, 24902280, 21435888, 107059200, 67977560, 245004000, 320311680, 534773760, 435984840, 1829206800, 943531280, 3187491840, 3151424000, 5466151440, 3559590240, 13703577600 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

a(n)=J_8(n)/J_1(n)=J_8(n)/phi(n)=A069093(n)/A000010(n), where J_k is the k-th Jordan Totient Function [From Enrique Pérez Herrero, Oct 28 2010]

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

Table of n, a(n) for n=1..24.

MATHEMATICA

A160908[n_]:=DivisorSum[n, MoebiusMu[n/# ]*#^(9-1)/EulerPhi[n]&] [From Enrique Pérez Herrero, Oct 28 2010]

CROSSREFS

Cf. A000010, A007434, A059376, A059377, A059378, A069091, A069092, A069093, A069094, A069095, A001615, A160889, A160891, A160893, A160895, A160897, A160960, A160972, A161010, A161025, A161139, A161167, A161213, A065958, A065959, A065960 [From Enrique Pérez Herrero, Oct 28 2010]

Sequence in context: A236792 A204738 A206048 * A038995 A068024 A028524

Adjacent sequences:  A160905 A160906 A160907 * A160909 A160910 A160911

KEYWORD

nonn,mult

AUTHOR

N. J. A. Sloane, Nov 19 2009

EXTENSIONS

Definition corrected by Enrique Pérez Herrero, Oct 28 2010

STATUS

approved

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Last modified November 25 18:10 EST 2014. Contains 250000 sequences.