A142616 - OEIS

%I #7 Sep 08 2022 08:45:37

%S 131,241,461,571,1231,1451,2111,2221,2441,2551,3541,3761,4091,4201,

%T 4421,4751,4861,5081,5521,5741,5851,6841,8161,8821,9041,9151,9371,

%U 9811,10141,10691,11131,11351,11681,12011,12451,12671,12781,13001,13331,13441,14321

%N Primes congruent to 21 mod 55.

%H Vincenzo Librandi, <a href="/A142616/b142616.txt">Table of n, a(n) for n = 1..1000</a>

%t Select[Prime[Range[2500]], MemberQ[{21}, Mod[#, 55]] &] (* _Vincenzo Librandi_, Aug 31 2012 *)

%o (Magma) [p: p in PrimesUpTo(16000) | p mod 55 eq 21]; // _Vincenzo Librandi_, Aug 31 2012

%Y Cf. A000040.

%K nonn,easy

%O 1,1

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