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Numbers k such that k^5 + 6^k is prime.
1

%I #31 Aug 10 2024 21:39:19

%S 1,11,41,121,157,5317,58247,74741

%N Numbers k such that k^5 + 6^k is prime.

%C Corresponding primes are in A075984.

%t k = 1; lst = {}; While[k < 30001, If[ PrimeQ[k^5 + 6^k], AppendTo[lst, k]; Print@ k]; k++]; lst (* _Robert G. Wilson v_, Dec 16 2010 *)

%t Select[Range[5500],PrimeQ[#^5+6^#]&] (* _Harvey P. Dale_, Feb 14 2018 *)

%o (Magma) [n: n in [0..900] | IsPrime(n^5+6^n)]; // _Vincenzo Librandi_, Dec 16 2010

%o (PARI) is(n)=ispseudoprime(n^5+6^n) \\ _Charles R Greathouse IV_, Jun 12 2017

%K nonn,more

%O 1,2

%A _Zak Seidov_, Oct 17 2002

%E a(7)-a(8) from _Michael S. Branicky_, Aug 10 2024