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A259310
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Primes of the form: 1 + sigma(n)^4.
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3
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2, 257, 1297, 614657, 331777, 331777, 160001, 331777, 9834497, 5308417, 8503057, 5308417, 9834497, 65610001, 5308417, 8503057, 40960001, 65610001, 29986577, 384160001, 40960001, 303595777, 1049760001, 65610001, 1944810001, 3782742017, 1944810001, 1049760001
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OFFSET
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1,1
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COMMENTS
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These primes are neither sorted nor uniqued. They are listed in the order found in A259308.
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LINKS
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FORMULA
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MAPLE
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MATHEMATICA
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Select[Table[1 + DivisorSigma[1, n]^4, {n, 10000}], PrimeQ]
Select[Table[Cyclotomic[8, DivisorSigma[1, n]], {n, 10000}], PrimeQ]
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PROG
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(Magma) [a: n in [1..150] | IsPrime(a) where a is 1 + SumOfDivisors(n)^4]; // Vincenzo Librandi, Jun 24 2015
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CROSSREFS
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KEYWORD
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easy,nonn
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AUTHOR
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STATUS
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approved
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