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%I #21 Oct 10 2024 01:10:25
%S 2,4,6,8,24,28,36,54,92,154,234,442,1138,2408,58564
%N Numbers k such that 5^k + k^4 is prime.
%t Select[Range[0, 10000, 2], PrimeQ[(5^# + #^4)] &]
%o (Magma) /* The code gives only the terms up to 442: */ [n: n in [0..1000 by 2] | IsPrime(5^n + n^4)];
%o (PARI) is(n)=ispseudoprime(5^n+n^4) \\ _Charles R Greathouse IV_, Jul 01 2013
%Y Cf. A182359, A059802.
%K nonn,more
%O 1,1
%A _Vincenzo Librandi_, Nov 26 2012
%E a(15) from _Michael S. Branicky_, Oct 09 2024