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A017693 Numerator of sum of -15th powers of divisors of n. 3
1, 32769, 14348908, 1073774593, 30517578126, 13061093507, 4747561509944, 35185445863425, 205891146443557, 500015258805447, 4177248169415652, 3851873211923611, 51185893014090758, 19446605389919367, 48654880101420712 (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[15, n]/n^15], {n, 1, 20}] (* G. C. Greubel, Nov 06 2018 *)

PROG

(PARI) vector(20, n, numerator(sigma(n, 15)/n^15)) \\ G. C. Greubel, Nov 06 2018

(MAGMA) [Numerator(DivisorSigma(15, n)/n^15): n in [1..20]]; // G. C. Greubel, Nov 06 2018

CROSSREFS

Cf. A017694.

Sequence in context: A183817 A303267 A323545 * A013963 A036093 A217357

Adjacent sequences:  A017690 A017691 A017692 * A017694 A017695 A017696

KEYWORD

nonn,frac

AUTHOR

N. J. A. Sloane

STATUS

approved

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Last modified May 29 10:05 EDT 2020. Contains 334699 sequences. (Running on oeis4.)