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A017712 Denominator of sum of -24th powers of divisors of n. 73


%S 1,16777216,282429536481,281474976710656,59604644775390625,

%T 2369190669160808448,191581231380566414401,4722366482869645213696,

%U 79766443076872509863361,500000000000000000000000,9849732675807611094711841

%N Denominator of sum of -24th 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="/A017712/b017712.txt">Table of n, a(n) for n = 1..1000</a>

%t Table[Denominator[DivisorSigma[24, n]/n^24], {n, 1, 20}] (* _G. C. Greubel_, Nov 03 2018 *)

%o (PARI) a(n) = denominator(sigma(n, 24)/n^24); \\ _Michel Marcus_, Nov 01 2013

%o (MAGMA) [Denominator(DivisorSigma(24,n)/n^24): n in [1..20]]; // _G. C. Greubel_, Nov 03 2018

%Y Cf. A017711.

%K nonn,frac

%O 1,2

%A _N. J. A. Sloane_

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Last modified December 10 00:54 EST 2019. Contains 329885 sequences. (Running on oeis4.)