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%I #23 Oct 24 2024 14:33:51
%S 0,1,2,4,5,10,12,14,24,34,37,52,56,65,68,96,106,128,156,169,236,254,
%T 481,618,641,672,700,774,1274,1625,1841,4650,6030,8372,8760,9173,
%U 12776,13873,25214,25548,33834,72005
%N Numbers k such that 22*3^k + 1 is prime.
%e If k=96 then 22*3^k + 1 is a prime with 48 digits.
%t Select[Range[0, 2000], PrimeQ[22*3^# + 1] &] (* _Stefan Steinerberger_, Aug 06 2006 *)
%o (Magma) [ n: n in [0..3000] | IsPrime(22*3^n + 1) ]; // _Vincenzo Librandi_, Jan 31 2011
%o (PARI) is(n)=ispseudoprime(22*3^n+1) \\ _Charles R Greathouse IV_, Jun 13 2017
%Y Cf. A003306.
%K nonn,more
%O 1,3
%A _Parthasarathy Nambi_, Aug 04 2006
%E More terms from _Stefan Steinerberger_, Aug 06 2006
%E a(32)-a(41) from _Michael S. Branicky_, Jul 14 2023
%E a(42) from _Michael S. Branicky_, Oct 24 2024