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%I #18 Sep 08 2022 08:45:21
%S 3,5,9,15,17,27,29,33,39,47,53,59,63,65,69,77,87,89,93,95,99,105,107,
%T 117,125,129,135,137,143,149,155,165,183,185,195,203,209,213,225,227,
%U 237,243,245,267,275,285,287,297,303,305,315,323,327,329,333,339,345
%N Numbers n such that 7*n + 8 is prime.
%C One less than the associated entry in A024905.
%e If n=125 then 7*n + 8 = 883 (prime).
%p A111249:=n->`if`(isprime(7*n+8), n, NULL): seq(A111249(n), n=1..10^3); # _Wesley Ivan Hurt_, Feb 13 2017
%t Select[Range[1,351,2], PrimeQ[7#+8]&] (* _Harvey P. Dale_, Sep 11 2016 *)
%o (Magma) [n: n in [0..100000] | IsPrime(7*n+8)] // _Vincenzo Librandi_, Nov 13 2010
%o (PARI) is(n)=isprime(7*n+8) \\ _Charles R Greathouse IV_, Feb 14 2017
%Y Cf. A024900, A024902, A024905, A105772.
%K nonn
%O 1,1
%A _Parthasarathy Nambi_, Oct 31 2005