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A197038
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Numbers k such that (2^k + 3^k)/97 is prime.
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0
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OFFSET
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1,1
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LINKS
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EXAMPLE
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a(1) = 12 => (2^12+3^12)/97 = 5521 is prime ;
(2^a(2)+3^a(2))/97 has 195 digits ;
(2^a(3)+3^a(3))/97 has 207 digits ;
(2^a(4)+3^a(4))/97 has 436 digits ;
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MATHEMATICA
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lst={}; Do[If[PrimeQ[(2^k+3^k)/97], AppendTo[lst, k]], {k, 1000}]; lst
Select[Range[10000], PrimeQ[(2^#+3^#)/97]&] (* Harvey P. Dale, Aug 22 2013 *)
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PROG
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CROSSREFS
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KEYWORD
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nonn,hard
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AUTHOR
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STATUS
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approved
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