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A127908
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Primes of form (3^n + 2^n)/5.
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1
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7, 463, 35839, 798167678837469920188160718521149336927, 24665899002341798194980052306171212216360861465143461865961807325057879, 5001149050738853423183653309332375420192266379562546200601855155172715420590196078603421469034502777938287
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OFFSET
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1,1
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COMMENTS
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Numbers n such that (2^n + 3^n)/5 is prime are listed in A057469 = {3, 7, 11, 83, 149, 223, 599, 647, 1373, 8423, ...}.
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LINKS
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FORMULA
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MATHEMATICA
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Do[f=(2^n+3^n)/5; If[PrimeQ[f], Print[{n, f}]], {n, 1, 1000}]
Select[Table[(3^n+2^n)/5, {n, 500}], PrimeQ] (* Harvey P. Dale, Aug 07 2019 *)
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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