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A034496
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Sum of n-th powers of divisors of 8.
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3
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4, 15, 85, 585, 4369, 33825, 266305, 2113665, 16843009, 134480385, 1074791425, 8594130945, 68736258049, 549822930945, 4398314962945, 35185445863425, 281479271743489, 2251816993685505, 18014467229220865
(list; graph; refs; listen; history; internal format)
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OFFSET
| 0,1
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COMMENTS
| Conjecture: No primes in this sequence (checked for first 10000 terms). [From Artur Jasinski (grafix(AT)csl.pl), Sep 23 2008]
All terms are composite because a(n) = (1 + 2^n) (1 + 4^n). [From T. D. Noe (noe(AT)sspectra.com), Apr 26 2010]
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LINKS
| T. D. Noe, Table of n, a(n) for n=0..200
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PROG
| (Other) sage: [sigma(8, n)for n in xrange(0, 19)] # [From Zerinvary Lajos (zerinvarylajos(AT)yahoo.com), Jun 04 2009]
(PARI) a(n)=sigma(8, n) \\ Charles R Greathouse IV, May 16, 2011
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CROSSREFS
| Sequence in context: A151379 A130679 A107874 * A079155 A076900 A081011
Adjacent sequences: A034493 A034494 A034495 * A034497 A034498 A034499
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KEYWORD
| nonn,easy
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AUTHOR
| N. J. A. Sloane (njas(AT)research.att.com).
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