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A017701 Numerator of sum of -19th powers of divisors of n. 3
1, 524289, 1162261468, 274878431233, 19073486328126, 50780075233021, 11398895185373144, 144115462954287105, 1350851718835253557, 5000009536743426207, 61159090448414546292, 79870152251600907511 (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..10000

MATHEMATICA

Table[Numerator[DivisorSigma[19, n]/n^19], {n, 1, 20}] (* G. C. Greubel, Nov 05 2018 *)

PROG

(PARI) vector(20, n, numerator(sigma(n, 19)/n^19)) \\ G. C. Greubel, Nov 05 2018

(MAGMA) [Numerator(DivisorSigma(19, n)/n^19): n in [1..20]]; // G. C. Greubel, Nov 05 2018

CROSSREFS

Cf. A017702.

Sequence in context: A010807 A236227 A320345 * A013967 A036097 A254039

Adjacent sequences:  A017698 A017699 A017700 * A017702 A017703 A017704

KEYWORD

nonn,frac

AUTHOR

N. J. A. Sloane

STATUS

approved

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Last modified March 30 16:16 EDT 2020. Contains 333127 sequences. (Running on oeis4.)