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%I #30 Sep 08 2022 08:45:02
%S 0,1,2,3,5,7,10,11,13,16,28,32,56,57,62,95,111,160,308,323,855,880,
%T 1081,1095,1288,2635,2822,2948,3195,7702,8823,10751,11572,12718,14587,
%U 20445,26863,28501,29086,30926,37671,38450,57541,81350,214250
%N Numbers k such that 5*3^k + 2 is prime.
%C 214250 also belongs to the sequence (but interval 35000-209600 was not searched). - _Serge Batalov_, Oct 30 2010
%C a(45) > 2*10^5. - _Robert Price_, May 16 2015
%C Confirmed a(45) = 214250. - _Robert Price_, May 21 2015
%C a(46) > 215000. - _Robert Price_, May 21 2015
%t Do[ If[ PrimeQ[ 5*3^n + 2 ], Print[ n ] ], {n, 0, 7550} ]
%t Select[Range[0, 2 10^3], PrimeQ[5 3^# + 2] &] (* _Vincenzo Librandi_, May 16 2015 *)
%o (Magma) [n: n in [0..1000] | IsPrime(5*3^n+2)]; // _Vincenzo Librandi_, May 16 2015
%o (PARI) is(n)=ispseudoprime(5*3^n+2) \\ _Charles R Greathouse IV_, Jun 13 2017
%o (PFGW) ABC2 5*3^$a + 2
%o a: from 0 to 10000 // _Jinyuan Wang_, Feb 01 2020
%Y Cf. A058591 (5*3^k - 2 is prime).
%K nonn,more
%O 1,3
%A _Robert G. Wilson v_, Dec 26 2000
%E More PRP terms from _Serge Batalov_, Oct 30 2010
%E a(41)-a(44) from _Robert Price_, May 16 2015
%E a(1)=0 prepended by _Vincenzo Librandi_, May 16 2015
%E a(45) discovered by Serge Batalov added by _Robert Price_, May 21 2015
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