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 A132237 Primes congruent to {7, 23} mod 30. 4

%I

%S 7,23,37,53,67,83,97,113,127,157,173,233,263,277,293,307,337,353,367,

%T 383,397,443,457,487,503,547,563,577,593,607,653,683,727,743,757,773,

%U 787,863,877,907,937,953,967,983,997,1013,1087,1103

%N Primes congruent to {7, 23} mod 30.

%C Up to 4913, there are more primes of this form than composites. See also A132231 and A227869 (congruent to 7 only). - _M. F. Hasler_, Nov 02 2013

%H Vincenzo Librandi, <a href="/A132237/b132237.txt">Table of n, a(n) for n = 1..1000</a>

%H C. K. Caldwell, <a href="http://primes.utm.edu">The Prime Pages</a>.

%H Omar E. Pol, <a href="http://www.polprimos.com">Determinacion geometrica de los numeros primos y perfectos</a>.

%t Select[Prime[Range[1000]],MemberQ[{7,23},Mod[#,30]]&] (* _Vincenzo Librandi_, Aug 14 2012 *)

%o (MAGMA) [ p: p in PrimesUpTo(1300) | p mod 30 in [7, 23] ]; // _Vincenzo Librandi_, Aug 14 2012

%o (PARI) is_A132237(n)=setsearch([7,23],n%30)&&isprime(n) \\ - _M. F. Hasler_, Nov 02 2013

%Y Cf. A000040, A007510, A039949, A068229, A129807.

%K easy,nonn

%O 1,1

%A _Omar E. Pol_, Aug 15 2007

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Last modified December 11 02:20 EST 2019. Contains 329910 sequences. (Running on oeis4.)