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%I #15 Sep 08 2022 08:46:03
%S 2,16,74,164,518,796,8756,12598
%N Numbers k such that 4^k + k^4 - 1 is prime.
%C a(9) > 10^5. - _Robert Price_, Feb 04 2014
%t Select[Range[0, 5000], PrimeQ[4^# + #^4 - 1] &]
%o (Magma) [n: n in [0..800] | IsPrime(4^n+n^4-1)];
%o (PARI) is(n)=ispseudoprime(4^n+n^4-1) \\ _Charles R Greathouse IV_, Jun 13 2017
%Y Cf. A100357, A215434-A215437, A215439-A215446, A216375.
%K nonn
%O 1,1
%A _Vincenzo Librandi_, Sep 07 2012
%E a(7)-a(8) from _Robert Price_, Feb 04 2014