%I #57 Jul 29 2013 12:02:05
%S 7,31,103,223,503,1171,1973,4111,4729
%N Numbers n such that (13^n + 2^n)/15 is prime.
%C All terms are prime.
%C a(10) > 10^5.
%t Select[Prime[Range[1, 100000]], PrimeQ[(13^# + 2^#)/15]&]
%o (PARI) forprime(p=3,10^6, if(ispseudoprime((13^p + 2^p)/15), print1(p,", ") ) ); \\ _Joerg Arndt_, Jul 29 2013
%Y Cf. A125956, A125957, A057159, A128071, A213176.
%K nonn,hard,more
%O 1,1
%A _Robert Price_, May 05 2013
%E Removed incorrect first term of "2".
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