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Search: id:A017680
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| A017680 |
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Denominator of sum of -8 th powers of divisors of n. |
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+0
2
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| 1, 256, 6561, 65536, 390625, 839808, 5764801, 16777216, 43046721, 50000000, 214358881, 71663616, 815730721, 737894528, 2562890625, 4294967296, 6975757441, 11019960576, 16983563041, 12800000000
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OFFSET
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1,2
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COMMENT
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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.
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CROSSREFS
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Cf. A017679.
Sequence in context: A077072 A128698 A016900 this_sequence A001016 A050755 A046457
Adjacent sequences: A017677 A017678 A017679 this_sequence A017681 A017682 A017683
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KEYWORD
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nonn,frac
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AUTHOR
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N. J. A. Sloane (njas(AT)research.att.com).
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