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%I #14 Mar 12 2023 08:48:23
%S 1,4,10,52,112,212,346,406,512,13904,76610,89746,114892
%N Numbers k such that 3^k - k^3 is prime.
%C Terms <= 512 correspond to certified primes. Next term after 13904 is greater than 20000.
%e 4 is a term because 3^4 - 4^3 = 17 is prime.
%e 3^10 - 10^3 = 58049 is prime, hence 10 is a term.
%t Do[If[PrimeQ[3^n - n^3], Print[n]], {n, 1, 20000}]
%o (PARI) is(n)=isprime(3^n-n^3) \\ _Charles R Greathouse IV_, Feb 17 2017
%K hard,more,nonn
%O 1,2
%A _Ryan Propper_, Jun 26 2005
%E Two more terms from _Donovan Johnson_, Feb 26 2008
%E a(13) from Norbert Schneider submitted by _Robert Price_, Mar 16 2019
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