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A017696 Denominator of sum of -16th powers of divisors of n. 3
1, 65536, 43046721, 4294967296, 152587890625, 1410554953728, 33232930569601, 281474976710656, 1853020188851841, 5000000000000000, 45949729863572161, 30814043149172736, 665416609183179841 (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[Denominator[DivisorSigma[16, n]/n^16], {n, 1, 20}] (* G. C. Greubel, Nov 05 2018 *)

PROG

(PARI) vector(20, n, denominator(sigma(n, 16)/n^16)) \\ G. C. Greubel, Nov 05 2018

(MAGMA) [Denominator(DivisorSigma(16, n)/n^16): n in [1..20]]; // G. C. Greubel, Nov 05 2018

CROSSREFS

Cf. A017695.

Sequence in context: A016808 A175924 A016904 * A211199 A010804 A276108

Adjacent sequences:  A017693 A017694 A017695 * A017697 A017698 A017699

KEYWORD

nonn,frac

AUTHOR

N. J. A. Sloane

STATUS

approved

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Last modified March 29 20:20 EDT 2020. Contains 333117 sequences. (Running on oeis4.)