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%I #36 Mar 15 2023 06:47:59
%S 1,2,3,5,8,10,19,27,79,198,565,787,2183,3811,4748,6210,7887,8965,
%T 13303,20125,23433,28797
%N Numbers k such that 6^k + 17 is prime.
%C a(20) > 14000. - _Daniel Starodubtsev_, Apr 17 2020
%e 3 is in the sequence because 6^3 + 17 = 233, which is prime.
%o (PARI) lista(nn)=for(k=0,nn,if(ispseudoprime(6^k+17),print1(k", ")))
%Y Cf. A013600, A013607, A059614, A145106, A182331, A217351, A217352.
%K nonn,more,hard,less
%O 1,2
%A _Daniel Starodubtsev_, Aug 06 2019
%E a(17)-a(18) from _Daniel Starodubtsev_, Mar 16 2020
%E a(19) from _Daniel Starodubtsev_, Apr 17 2020
%E a(20)-a(22) from _Michael S. Branicky_, Mar 14 2023