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%I #4 Jun 13 2017 12:44:40
%S 1,2,6,16,5436,6238
%N Numbers n such that 3*n^n-1 is prime.
%C Six terms found and primes proved by PrimeForm ([N+1, Brillhart-Lehmer-Selfridge]). 3*6238^6238-1 has 23674 digits. No more terms <= 8800.
%o (PARI) is(n)=ispseudoprime(3*n^n-1) \\ _Charles R Greathouse IV_, Jun 13 2017
%Y Cf. A118306, A110931.
%K hard,more,nonn
%O 1,2
%A _Rick L. Shepherd_, Apr 22 2006
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