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%I #12 Sep 08 2022 08:46:17
%S 23,15619,244140613
%N Primes of the form 5^n - n.
%C Corresponding n are given in A058046.
%C The next term has 254 digits.
%t Select[Table[5^n - n, {n, 400}], PrimeQ]
%o (Magma) [a: n in [0..400] | IsPrime(a) where a is 5^n-n];
%o (PARI) forstep(n=2,1e4,2, if(ispseudoprime(t=5^n-n), print1(t", "))) \\ _Charles R Greathouse IV_, Jun 08 2016
%Y Cf. primes of the form k^n - n: A081296 (k=2), A224420 (k=3), A224451 (k=4), this sequence (k=5), A273941 (k=6), A224468 (k=7), A224469 (k=8).
%Y Cf. A058046.
%K nonn,bref
%O 1,1
%A _Vincenzo Librandi_, Jun 05 2016