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%I #4 Jun 13 2017 12:57:38
%S 0,1,819,1449,1677,13319
%N Numbers n such that 2*41^n + 1 is prime.
%C Primes found and proved by PrimeForm. No more terms up to 30000.
%o (PARI) is(n)=ispseudoprime(2*41^n+1) \\ _Charles R Greathouse IV_, Jun 13 2017
%Y Cf. A141802.
%K hard,nonn
%O 1,3
%A _Rick L. Shepherd_, Aug 02 2008