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A114973
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Numbers n such that 5^n + n^5 is a semiprime.
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4
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OFFSET
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1,2
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COMMENTS
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LINKS
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EXAMPLE
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2 is OK because 5^2 + 2^5 = 25 + 32 = 57 = 3*19 (semiprime).
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MATHEMATICA
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PROG
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(Magma)IsSemiprime:=func< n|&+[k[2]: k in Factorization(n)] eq 2 >; [n: n in [1..85]|IsSemiprime(5^n+n^5)]; // Vincenzo Librandi, Dec 16 2010
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CROSSREFS
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KEYWORD
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nonn,more,hard
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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