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%I #17 Jun 13 2017 14:26:06
%S 1,2,4,7,10,19,22,44,62,76,122,2191,3134,9244,40999,48230
%N Numbers n such that 9^n + 8 is prime.
%C Contains exactly the halved even terms of A217136. - _Bruno Berselli_, Oct 04 2012
%t Select[Range[5000], PrimeQ[9^# + 8] &]
%o (PARI) is(n)=ispseudoprime(9^n+8) \\ _Charles R Greathouse IV_, Jun 13 2017
%Y Cf. A090649, A177093, A217136, A217384.
%K nonn,hard,more
%O 1,2
%A _Vincenzo Librandi_, Oct 04 2012
%E a(14) from _Bruno Berselli_, Oct 05 2012
%E a(15)-a(16) derived from A217136 by _Robert Price_, May 19 2015