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Primes of the form 30n - 13.
33

%I #46 Sep 08 2022 08:44:53

%S 17,47,107,137,167,197,227,257,317,347,467,557,587,617,647,677,797,

%T 827,857,887,947,977,1097,1187,1217,1277,1307,1367,1427,1487,1607,

%U 1637,1667,1697,1787,1847,1877,1907,1997,2027,2087,2207,2237,2267,2297,2357,2417

%N Primes of the form 30n - 13.

%C This linear form produces the most primes for n between 1 and 1000 (411/1000).

%C Primes congruent to 17 (mod 30). - _Omar E. Pol_, Aug 15 2007

%C Primes ending in 7 with (SOD-1)/3 non-integer where SOD is sum of digits. - _Ki Punches_

%C Or primes p such that (p mod 3) = (p mod 5) and (p mod 2) <> (p mod 3), (p > 2). - _Mikk Heidemaa_, Jan 19 2016

%D C. Clawson, Mathematical Mysteries, Plenum Press, 1996, p. 173

%H Vincenzo Librandi, <a href="/A039949/b039949.txt">Table of n, a(n) for n = 1..1000</a>

%F a(n) = A158648(n)*30 + 17. - _Ray Chandler_, Apr 07 2009

%F Intersection of A030432 and A007528. - _Ray Chandler_, Apr 07 2009

%F a(n) = A141860(n+1). - _Zak Seidov_, Apr 15 2015

%t Select[Prime[Range[1000]],MemberQ[{17},Mod[#,30]]&] (* _Vincenzo Librandi_, Aug 04 2012 *)

%t Select[Range[17,3000,30],PrimeQ] (* _Zak Seidov_, Apr 15 2015 *)

%o (Magma) [p: p in PrimesUpTo(3000) | p mod 30 in [17]]; // _Vincenzo Librandi_, Aug 04 2012

%o (PARI) select(n->n%30==17, primes(500)) \\ _Charles R Greathouse IV_, Apr 28 2015

%Y Cf. A132230-A132236, A141860.

%K nonn,easy

%O 1,1

%A _Felice Russo_

%E Extended by _Ray Chandler_, Apr 07 2009