|
Search: id:A017681
|
|
|
| A017681 |
|
Numerator of sum of -9 th powers of divisors of n. |
|
+0
2
|
|
| 1, 513, 19684, 262657, 1953126, 93499, 40353608, 134480385, 387440173, 500976819, 2357947692, 1292535097, 10604499374, 2587675113, 1423901192, 68853957121, 118587876498, 7361363287, 322687697780
(list; graph; listen)
|
|
|
OFFSET
|
1,2
|
|
|
COMMENT
|
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. - comment from Ahmed Fares (ahmedfares(AT)my-deja.com), Apr 05 2001.
|
|
CROSSREFS
|
Cf. A017682.
Sequence in context: A066697 A076338 A111344 this_sequence A013957 A036087 A007487
Adjacent sequences: A017678 A017679 A017680 this_sequence A017682 A017683 A017684
|
|
KEYWORD
|
nonn,frac
|
|
AUTHOR
|
N. J. A. Sloane (njas(AT)research.att.com).
|
|
|
Search completed in 0.002 seconds
|
