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A160893 Sum_{d|n} Moebius(n/d)*d^(b-1)/phi(n) for b = 6. 8
1, 31, 121, 496, 781, 3751, 2801, 7936, 9801, 24211, 16105, 60016, 30941, 86831, 94501, 126976, 88741, 303831, 137561, 387376, 338921, 499255, 292561, 960256, 488125, 959171, 793881, 1389296, 732541, 2929531, 954305, 2031616, 1948705 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

a(n)=J_5(n)/J_1(n)=J_5(n)/phi(n)=A059378(n)/A000010(n), where J_k is the k-th Jordan Totient Function [From Enrique Pérez Herrero, Oct 19 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

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

FORMULA

Multiplicative with a(p^e) = p^(4e-4)*(1+p+p^2+p^3+p^4). - R. J. Mathar, Jul 10 2011

MAPLE

A160893 := proc(n) a := 1 ; for f in ifactors(n)[2] do p := op(1, f) ; e := op(2, f) ; a := a*p^(4*e-4)*(1+p+p^2+p^3+p^4) ; end do; a; end proc: # R. J. Mathar, Jul 10 2011

MATHEMATICA

A160893[n_]:=DivisorSum[n, MoebiusMu[n/# ]*#^(6-1)/EulerPhi[n]&] [From Enrique Pérez Herrero, Oct 19 2010]

CROSSREFS

Cf. A160891, A160895, A160897, A160960, A160972, A161010, A161025, A161139 , A161167, A161213, A065958, A065959, A065960 [From Enrique Pérez Herrero, Oct 19 2010]

Sequence in context: A010019 A131550 A158558 * A202994 A038992 A068021

Adjacent sequences:  A160890 A160891 A160892 * A160894 A160895 A160896

KEYWORD

nonn,mult

AUTHOR

N. J. A. Sloane, Nov 19 2009

EXTENSIONS

Definition corrected by Enrique Perez Herrero, Oct 19 2010

STATUS

approved

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Last modified October 23 13:13 EDT 2014. Contains 248464 sequences.