%I #25 May 02 2023 03:21:37
%S 2,3,4,5,8,12,15,17,20,21,45,48,87,97,113,120,172,217,228,276,312,580,
%T 692,1132,1588,1668,2576,2591,3780,4311,4412,6205,11952,19897,19941,
%U 20525,22821,44757,62833
%N Numbers k such that 3*2^k - 7 is prime.
%C Next term > 12000. - _Vincenzo Librandi_, Sep 29 2012
%t Do[ If[ PrimeQ[ 3*2^n - 7 ], Print[n] ], {n, 3000} ]
%t Select[Range[6500], PrimeQ[(3*2^# - 7)] &] (* _Vincenzo Librandi_, Sep 29 2012 *)
%o (PARI) is(n)=ispseudoprime(3*2^n-7) \\ _Charles R Greathouse IV_, Jun 13 2017
%Y Cf. A059746.
%K nonn,more
%O 1,1
%A _Robert G. Wilson v_, Feb 10 2001
%E a(29)-a(32) from _Vincenzo Librandi_, Sep 29 2012
%E a(33) from _Bruno Berselli_, Sep 30 2012
%E a(34)-a(39) from _Michael S. Branicky_, May 01 2023
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