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A017696 Denominator of sum of -16th powers of divisors of n. 3


%S 1,65536,43046721,4294967296,152587890625,1410554953728,

%T 33232930569601,281474976710656,1853020188851841,5000000000000000,

%U 45949729863572161,30814043149172736,665416609183179841

%N Denominator of sum of -16th 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="/A017696/b017696.txt">Table of n, a(n) for n = 1..10000</a>

%t Table[Denominator[DivisorSigma[16, n]/n^16], {n, 1, 20}] (* _G. C. Greubel_, Nov 05 2018 *)

%o (PARI) vector(20, n, denominator(sigma(n, 16)/n^16)) \\ _G. C. Greubel_, Nov 05 2018

%o (MAGMA) [Denominator(DivisorSigma(16,n)/n^16): n in [1..20]]; // _G. C. Greubel_, Nov 05 2018

%Y Cf. A017695.

%K nonn,frac

%O 1,2

%A _N. J. A. Sloane_

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Last modified June 1 00:27 EDT 2020. Contains 334756 sequences. (Running on oeis4.)