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%I A056799 #25 Jul 05 2020 08:23:09
%S A056799 1,4,5,11,26,29,38,65,166,490,641,2300,9440,44741,65296,161930,586240
%N A056799 Numbers n such that 8*9^n +1 is prime.
%C A056799 The even members of A005538, halved. - _Jeppe Stig Nielsen_, Oct 13 2019
%t A056799 Do[If[PrimeQ[8*9^n + 1], Print[n]], {n, 0, 1000}]
%t A056799 Select[Range[3000], PrimeQ[8 9^# + 1] &] (* _Vincenzo Librandi_, Sep 28 2012 *)
%o A056799 (PARI) is(n)=ispseudoprime(8*9^n+1) \\ _Charles R Greathouse IV_, Mar 01 2017
%Y A056799 Cf. A005538.
%K A056799 nonn,more
%O A056799 1,2
%A A056799 _Robert G. Wilson v_, Aug 22 2000
%E A056799 a(12) from _Vincenzo Librandi_, Sep 28 2012
%E A056799 a(13)-a(16) from _Robert Price_, Feb 22 2016
%E A056799 a(17) from _Paul S. Vanderveen_, Jul 04 2020

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