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%I #22 Nov 20 2022 15:59:53
%S 31,73,157,199,241,283,367,409,577,619,661,787,829,997,1039,1123,1249,
%T 1291,1459,1543,1627,1669,1753,1879,2089,2131,2341,2383,2467,2551,
%U 2593,2677,2719,2803,2887,2971,3181,3307,3391,3433,3517,3559,3643,3727,3769,3853
%N Primes congruent to 10 mod 21.
%H Vincenzo Librandi, <a href="/A141892/b141892.txt">Table of n, a(n) for n = 1..1000</a>
%F a(n) ~ 12n log n. - _Charles R Greathouse IV_, Jul 02 2016
%t Select[Range[10,5000,21],PrimeQ] (* _Vladimir Joseph Stephan Orlovsky_, Apr 04 2011 *)
%t Select[Prime[Range[600]],Mod[#,21]==10&] (* _Harvey P. Dale_, Nov 20 2022 *)
%o (Magma) [ p: p in PrimesUpTo(5000) | p mod 21 eq 10 ]; // _Vincenzo Librandi_, Apr 05 2011
%o (PARI) is(n)=isprime(n) && n%21==10 \\ _Charles R Greathouse IV_, Jul 02 2016
%Y Cf. A000040, A124826.
%K nonn,easy
%O 1,1
%A _N. J. A. Sloane_, Jul 11 2008