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%I #14 Sep 08 2022 08:44:43
%S 1,8388608,94143178827,70368744177664,11920928955078125,
%T 65810851921133568,27368747340080916343,590295810358705651712,
%U 8862938119652501095929,50000000000000000000000,895430243255237372246531
%N Denominator of sum of -23rd 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="/A017710/b017710.txt">Table of n, a(n) for n = 1..1000</a>
%t Table[Denominator[DivisorSigma[23, n]/n^23], {n, 1, 20}] (* _G. C. Greubel_, Nov 03 2018 *)
%o (PARI) a(n) = denominator(sigma(n, 23)/n^23); \\ _G. C. Greubel_, Nov 03 2018
%o (Magma) [Denominator(DivisorSigma(23,n)/n^23): n in [1..20]]; // _G. C. Greubel_, Nov 03 2018
%Y Cf. A017709.
%K nonn,frac
%O 1,2
%A _N. J. A. Sloane_