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Primes congruent to 3 mod 40.
1

%I #11 Sep 08 2022 08:45:35

%S 3,43,83,163,283,443,523,563,643,683,883,1123,1163,1283,1483,1523,

%T 1723,2003,2083,2203,2243,2683,2803,2843,2963,3083,3163,3203,3323,

%U 3643,3803,3923,4003,4243,4283,4363,4483,4523,4603,4643,4723,5003,5323,5443,5483

%N Primes congruent to 3 mod 40.

%H Vincenzo Librandi, <a href="/A142184/b142184.txt">Table of n, a(n) for n = 1..1000</a>

%F a(n) ~ 16n log n. - _Charles R Greathouse IV_, Jul 03 2016

%t Select[Prime[Range[2000]],MemberQ[{3},Mod[#,40]]&] (* _Vincenzo Librandi_, Aug 20 2012 *)

%t Select[Range[3,5500,40],Prime (* _Harvey P. Dale_, Jun 10 2015 *)

%o (Magma)[p: p in PrimesUpTo(7000) | p mod 40 eq 3]; // _Vincenzo Librandi_, Aug 20 2012

%o (PARI) is(n)=isprime(n) && n%40==3 \\ _Charles R Greathouse IV_, Jul 03 2016

%Y Cf. A000040.

%K nonn,easy

%O 1,1

%A _N. J. A. Sloane_, Jul 11 2008