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Primes congruent to 11, 13, 17 or 19 (mod 30).
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%I #15 Sep 08 2022 08:46:16

%S 11,13,17,19,41,43,47,71,73,79,101,103,107,109,131,137,139,163,167,

%T 191,193,197,199,223,227,229,251,257,281,283,311,313,317,347,349,373,

%U 379,401,409,431,433,439,461,463,467,491,499,521,523,557,587,613,617

%N Primes congruent to 11, 13, 17 or 19 (mod 30).

%F a(n) ~ 2n log n. - _Charles R Greathouse IV_, Apr 05 2016

%p select(isprime, [seq(seq(30*i+k, k = [11,13,17,19]), i=0..100)]); # _Robert Israel_, Apr 05 2016

%t Select[Prime[Range[200]],MemberQ[{11,13,17,19},Mod[#,30]]&] (* _Harvey P. Dale_, Aug 23 2017 *)

%o (PARI) is(n)=n\10%3==1 && isprime(n) \\ _Charles R Greathouse IV_, Apr 05 2016

%o (Magma) [p: p in PrimesUpTo(700) | p mod 30 in {11,13,17,19}]; // _Vincenzo Librandi_, Jan 04 2020

%Y Cf. A000040, A076746.

%K nonn,easy

%O 1,1

%A _J. M. Bergot_, Apr 05 2016