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A160892 ((2^b-1)/phi(n))*Sum_{d|n} Moebius(n/d)*d^(b-1) for b = 4. 0
15, 105, 195, 420, 465, 1365, 855, 1680, 1755, 3255, 1995, 5460, 2745, 5985, 6045, 6720, 4605, 12285, 5715, 13020, 11115, 13965, 8295, 21840, 11625, 19215, 15795, 23940, 13065, 42315, 14895, 26880, 25935, 32235, 26505, 49140, 21105, 40005 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

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..38.

FORMULA

a(n) = 15*A160889(n). - R. J. Mathar, Feb 07 2011

CROSSREFS

Sequence in context: A300295 A102791 A335672 * A061550 A174385 A185129

Adjacent sequences:  A160889 A160890 A160891 * A160893 A160894 A160895

KEYWORD

nonn

AUTHOR

N. J. A. Sloane, Nov 19 2009

STATUS

approved

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Last modified July 4 05:54 EDT 2020. Contains 335444 sequences. (Running on oeis4.)