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%I #11 Sep 08 2022 08:45:35
%S 5,61,89,173,229,257,313,397,509,593,677,733,761,929,1013,1069,1097,
%T 1153,1181,1237,1321,1433,1489,1601,1657,1741,1993,2161,2273,2357,
%U 2441,2609,2693,2749,2777,2833,2861,2917,3001,3169,3253,3449,3533,3617,3673,3701
%N Primes congruent to 5 mod 28.
%H Vincenzo Librandi, <a href="/A141967/b141967.txt">Table of n, a(n) for n = 1..1000</a>
%F a(n) ~ 12n log n. - _Charles R Greathouse IV_, Jul 03 2016
%t Select[Prime[Range[2000]],MemberQ[{5},Mod[#,28]]&] (* _Vincenzo Librandi_, Aug 17 2012 *)
%t Select[Range[5,4000,28],PrimeQ] (* _Harvey P. Dale_, Dec 31 2021 *)
%o (Magma) [p: p in PrimesUpTo(5000) | p mod 28 eq 5 ]; // _Vincenzo Librandi_, Aug 17 2012
%o (PARI) is(n)=isprime(n) && n%28==5 \\ _Charles R Greathouse IV_, Jul 03 2016
%Y Cf. A000040.
%K nonn,easy
%O 1,1
%A _N. J. A. Sloane_, Jul 11 2008