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A114301
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Numbers n such that 2^n + 3^n + 5^n + 7^n is a prime number.
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0
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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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2^3 + 3^3 + 5^3 + 7^3 = 503 (prime), thus 3 is in the sequence.
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MAPLE
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select(t -> isprime(2^t+3^t+5^t+7^t), [seq(i, i=1..10000, 2)]); # Robert Israel, May 03 2018
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MATHEMATICA
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Do[If[PrimeQ[2^n+3^n+5^n+7^n], Print[n]], {n, 1, 5000}]
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CROSSREFS
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KEYWORD
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hard,more,nonn
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AUTHOR
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EXTENSIONS
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a(7) from Joao Carlos Leandro da Silva (zxawyh66(AT)yahoo.com), Jun 01 2009
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STATUS
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approved
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