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A063784
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Primes obtained as a sum of cube of divisors of an integer.
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2
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73, 757, 1772893, 48551233240513, 378890487846991, 3156404483062657, 17390284913300671, 280343912759041771, 319913861581383373, 487014306953858713, 7824668707707203971, 8443914727229480773
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,1
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LINKS
| Harry J. Smith, Table of n, a(n) for n=1,...,1000
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FORMULA
| Primes of form p = DivisorSigma[3, x].
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EXAMPLE
| sigma[3,9]=1+27+729=757, a prime.
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PROG
| (PARI) { n=0; p=0; for (m=1, 10^9, p=nextprime(p+1); if(isprime(q=p^6 + p^3 + 1), write("b063784.txt", n++, " ", q); if (n==1000, break)) ) } [From Harry J. Smith (hjsmithh(AT)sbcglobal.net), Aug 31 2009]
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CROSSREFS
| A023194.
Sequence in context: A177514 A137835 * A066101 A169830 A100412 A197341
Adjacent sequences: A063781 A063782 A063783 * A063785 A063786 A063787
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KEYWORD
| nonn
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AUTHOR
| Labos E. (labos(AT)ana.sote.hu), Aug 17 2001
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