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 A017709 Numerator of sum of -23rd powers of divisors of n. 3
 1, 8388609, 94143178828, 70368752566273, 11920928955078126, 65810859767097521, 27368747340080916344, 590295880727458217985, 8862938119746644274757, 50000005960464481733367, 895430243255237372246532 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS 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 LINKS G. C. Greubel, Table of n, a(n) for n = 1..1000 MATHEMATICA Table[Numerator[Total[Divisors[n]^-23]], {n, 12}] (* Harvey P. Dale, Oct 19 2012 *) Table[Numerator[DivisorSigma[23, n]/n^23], {n, 1, 20}] (* G. C. Greubel, Nov 03 2018 *) PROG (PARI) a(n) = numerator(sigma(n, 23)/n^23); \\ G. C. Greubel, Nov 03 2018 (MAGMA) [Numerator(DivisorSigma(23, n)/n^23): n in [1..20]]; // G. C. Greubel, Nov 03 2018 CROSSREFS Cf. A017710. Sequence in context: A017710 A010811 A323660 * A013971 A036101 A283031 Adjacent sequences:  A017706 A017707 A017708 * A017710 A017711 A017712 KEYWORD nonn,frac AUTHOR STATUS approved

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Last modified December 6 06:34 EST 2019. Contains 329784 sequences. (Running on oeis4.)