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 A161167 a(n) = Sum_{d|n} Moebius(n/d)*d^(b-1)/phi(n) for b = 17. 3
 1, 65535, 21523360, 2147450880, 38146972656, 1410533397600, 5538821761600, 70367670435840, 308836690967520, 2499961853010960, 4594972986357216, 46220358372556800, 55451384098598320, 362986684146456000 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS a(n) is the number of lattices L in Z^16 such that the quotient group Z^16 / L is C_n. - Álvar Ibeas, Nov 26 2015 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 a(n) = J_16(n)/J_1(n) = J_16(n)/A000010(n), where J_k is the k-th Jordan Totient Function From Álvar Ibeas, Nov 26 2015: (Start) Multiplicative with a(p^e) = p^(15e-15) * (p^16-1) / (p-1). For squarefree n, a(n) = A000203(n^15). (End) MAPLE A161167 := proc(n)     add(numtheory[mobius](n/d)*d^16, d=numtheory[divisors](n)) ;     %/numtheory[phi](n) ; end proc: for n from 1 to 5000 do     printf("%d %d\n", n, A161167(n)) ; end do: # R. J. Mathar, Mar 15 2016 MATHEMATICA A161167[n_]:=DivisorSum[n, MoebiusMu[n/#]*#^(17-1)/EulerPhi[n]&]; Array[A161167, 20] PROG (PARI) vector(100, n, sumdiv(n^15, d, if(ispower(d, 16), moebius(sqrtnint(d, 16))*sigma(n^15/d), 0))) \\ Altug Alkan, Nov 26 2015 CROSSREFS Cf. A000203. Sequence in context: A075969 A075965 A011566 * A022532 A161195 A069391 Adjacent sequences:  A161164 A161165 A161166 * A161168 A161169 A161170 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 January 19 06:18 EST 2022. Contains 350464 sequences. (Running on oeis4.)