This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A017683 #20 Apr 02 2024 02:56:33 %S A017683 1,1025,59050,1049601,9765626,30263125,282475250,1074791425, %T A017683 3486843451,200195333,25937424602,10329823175,137858491850, %U A017683 144768565625,23066408612,1100586419201,2015993900450,3574014537275,6131066257802,5125005407613,16680163512500,13292930108525 %N A017683 Numerator of sum of -10th powers of divisors of n. %C A017683 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 A017683 G. C. Greubel, <a href="/A017683/b017683.txt">Table of n, a(n) for n = 1..10000</a> %F A017683 Numerators of coefficients in expansion of Sum_{k>=1} x^k/(k^10*(1 - x^k)). - _Ilya Gutkovskiy_, May 25 2018 %F A017683 From _Amiram Eldar_, Apr 02 2024: (Start) %F A017683 sup_{n>=1} a(n)/A017684(n) = zeta(10) (A013668). %F A017683 Dirichlet g.f. of a(n)/A017684(n): zeta(s)*zeta(s+10). %F A017683 Asymptotic mean: Limit_{m->oo} (1/m) * Sum_{k=1..m} a(k)/A017684(k) = zeta(11) (A013669). (End) %e A017683 1, 1025/1024, 59050/59049, 1049601/1048576, 9765626/9765625, 30263125/30233088, 282475250/282475249, ... %t A017683 Table[Numerator[Total[Divisors[n]^-10]],{n,20}] (* _Harvey P. Dale_, Sep 04 2018 *) %t A017683 Table[Numerator[DivisorSigma[10, n]/n^10], {n, 1, 20}] (* _G. C. Greubel_, Nov 07 2018 *) %o A017683 (PARI) vector(20, n, numerator(sigma(n, 10)/n^10)) \\ _G. C. Greubel_, Nov 07 2018 %o A017683 (Magma) [Numerator(DivisorSigma(10,n)/n^10): n in [1..20]]; // _G. C. Greubel_, Nov 07 2018 %Y A017683 Cf. A017684 (denominator), A013668, A013669. %K A017683 nonn,frac %O A017683 1,2 %A A017683 _N. J. A. Sloane_