A142606 - OEIS

%I #11 Sep 08 2022 08:45:36

%S 7,227,337,557,887,997,1217,1327,1657,1877,1987,2207,2647,3307,3527,

%T 3637,3967,4297,4517,4957,5507,6277,6607,6827,7487,7817,7927,8147,

%U 8807,9137,9467,9907,10457,10567,11117,11447,11777,11887,12107,12437,12547,13537

%N Primes congruent to 7 mod 55.

%H Vincenzo Librandi, <a href="/A142606/b142606.txt">Table of n, a(n) for n = 1..1000</a>

%F a(n) ~ 40n log n. - _Charles R Greathouse IV_, Jul 04 2016

%t Select[Prime[Range[2500]], MemberQ[{7}, Mod[#, 55]] &] (* _Vincenzo Librandi_, Aug 31 2012 *)

%t Select[Range[7,14000,55],PrimeQ] (* _Harvey P. Dale_, Dec 31 2013 *)

%o (Magma) [p: p in PrimesUpTo(16000) | p mod 55 eq 7]; // _Vincenzo Librandi_, Aug 31 2012

%o (PARI) is(n)=isprime(n) && n%55==7 \\ _Charles R Greathouse IV_, Jul 04 2016

%Y Cf. A000040.

%K nonn,easy

%O 1,1

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