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Primes p such that p+18 and p+36 are both prime.
2

%I #12 Sep 08 2022 08:45:41

%S 5,11,23,43,53,61,71,113,131,163,193,233,313,331,383,421,431,443,641,

%T 673,683,691,733,751,821,911,1013,1033,1051,1213,1283,1453,1531,1583,

%U 1601,1723,1741,1871,1913,1993,2063,2143,2203,2251,2381,2423,2441,2503

%N Primes p such that p+18 and p+36 are both prime.

%C A153418 INTERSECT A156104. [_Bruno Berselli_, Nov 01 2012]

%H Vincenzo Librandi, <a href="/A156109/b156109.txt">Table of n, a(n) for n = 1..1000</a>

%p a := proc (n) if isprime(ithprime(n)+18) = true and isprime(ithprime(n)+36) = true then ithprime(n) else end if end proc: seq(a(n), n = 1 .. 400); # _Emeric Deutsch_, Mar 02 2009

%t Select[Prime[Range[3000]], And @@ PrimeQ[{# + 18, # + 36}]&] (* _Vincenzo Librandi_, Oct 31 2012 *)

%o (Magma) [p: p in PrimesUpTo(3000)|IsPrime(p + 18) and IsPrime (p + 36)]; // _Vincenzo Librandi_, Oct 31 2012

%Y Cf. A153418, A156104.

%K nonn,easy

%O 1,1

%A _Vincenzo Librandi_, Feb 08 2009

%E More terms from _Emeric Deutsch_, Mar 02 2009