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A017692 Denominator of sum of -14th powers of divisors of n. 3

%I #12 Sep 08 2022 08:44:43

%S 1,16384,4782969,268435456,6103515625,39182082048,678223072849,

%T 4398046511104,22876792454961,10000000000000,379749833583241,

%U 213986410758144,3937376385699289,5556003412779008,5838585205078125

%N Denominator of sum of -14th powers of divisors of n.

%C Sum_{d|n} 1/d^k is equal to sigma_k(n)/n^k. So sequences A017665-A017712 also give the numerators and denominators of sigma_k(n)/n^k for k = 1..24. The power sums sigma_k(n) are in sequences A000203 (k=1), A001157-A001160 (k=2,3,4,5), A013954-A013972 for k = 6,7,...,24. - Ahmed Fares (ahmedfares(AT)my-deja.com), Apr 05 2001

%H G. C. Greubel, <a href="/A017692/b017692.txt">Table of n, a(n) for n = 1..10000</a>

%t Table[Denominator[DivisorSigma[14, n]/n^14], {n, 1, 20}] (* _G. C. Greubel_, Nov 06 2018 *)

%o (PARI) vector(20, n, denominator(sigma(n, 14)/n^14)) \\ _G. C. Greubel_, Nov 06 2018

%o (Magma) [Denominator(DivisorSigma(14,n)/n^14): n in [1..20]]; // _G. C. Greubel_, Nov 06 2018

%Y Cf. A017691.

%K nonn,frac

%O 1,2

%A _N. J. A. Sloane_

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Last modified April 19 07:38 EDT 2024. Contains 371782 sequences. (Running on oeis4.)