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A023274 Primes that remain prime through 3 iterations of function f(x) = 2x + 5.

%I A023274 #28 Sep 08 2022 08:44:47
%S A023274 13,31,37,67,73,181,367,541,661,997,1087,1117,1327,1861,2179,2293,
%T A023274 2473,2713,2719,3271,3727,4363,5281,5443,5749,7459,8089,8707,9109,
%U A023274 9181,9337,10357,10639,12553,13183,14923,16183,16249,17341,17419,17761,17923,17989
%N A023274 Primes that remain prime through 3 iterations of function f(x) = 2x + 5.
%C A023274 Primes p such that 2*p+5, 4*p+15 and 8*p+35 are also primes. - _Vincenzo Librandi_, Aug 04 2010
%H A023274 John Cerkan, <a href="/A023274/b023274.txt">Table of n, a(n) for n = 1..10000</a>
%F A023274 a(n) == 1 (mod 6). - _John Cerkan_, Sep 16 2016
%p A023274 select(t -> isprime(t) and isprime(2*t+5) and isprime(4*t+15) and isprime(8*t+35), [seq(t,t=7..20000,6)]);# _Robert Israel_, Sep 18 2016
%t A023274 Select[Prime@ Range@ 2100, Times @@ Boole@ PrimeQ@ Rest@ NestList[2 # + 5 &, #, 3] > 0 &] (* _Michael De Vlieger_, Sep 16 2016 *)
%o A023274 (Magma) [n: n in [1..100000] | IsPrime(n) and IsPrime(2*n+5) and IsPrime(4*n+15) and IsPrime(8*n+35)] // _Vincenzo Librandi_, Aug 04 2010
%Y A023274 Subsequence of A023205, A023243, and of A089038.
%K A023274 nonn
%O A023274 1,1
%A A023274 _David W. Wilson_