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Primes p such that 71*p + 34 is also prime.
2

%I #16 Sep 08 2022 08:45:40

%S 5,23,47,53,83,89,149,179,317,347,353,359,389,467,503,557,569,647,683,

%T 773,929,947,977,983,1019,1103,1193,1217,1229,1283,1307,1319,1439,

%U 1733,1847,1889,1907,2069,2153,2243,2309,2357,2393,2399,2417,2657,2687,2693

%N Primes p such that 71*p + 34 is also prime.

%H Vincenzo Librandi, <a href="/A154625/b154625.txt">Table of n, a(n) for n = 1..1000</a>

%p a := proc (n) if isprime(n) = true and isprime(71*n+34) = true then n else end if end proc: seq(a(n), n = 1 .. 3000); # _Emeric Deutsch_, Jan 26 2009

%t Select[Prime[Range[500]],PrimeQ[71#+34]&] (* _Harvey P. Dale_, Jun 04 2011 *)

%o (Magma) [p: p in PrimesUpTo(2800)| IsPrime(71*p + 34)]; // _Vincenzo Librandi_, Oct 30 2012

%Y Cf. A154624.

%K nonn,easy

%O 1,1

%A _Vincenzo Librandi_, Jan 17 2009

%E Extended by _Emeric Deutsch_, Jan 26 2009