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%I #25 Mar 13 2016 11:28:01
%S 2,3,5,7,61,97,101,257,2531,4783,5683,6317,8963,9463,9497,11593,15683,
%T 18757,23687,26251,29611,31271,36011,45497,45979,46853,54869,73379,
%U 92557,93761,104173,107857,107981,121607,134047,192091,196853,236729,285599,310081
%N Quadruple Hex-primes: let f(n) = A102489(n); then sequence lists primes p such that f(p), f(f(p)). f(f(f(p))) and f(f(f(f(p)))) are also primes.
%C The sequence is a subset of sequences A103144, A237438, and A237439.
%H Harvey P. Dale, <a href="/A237440/b237440.txt">Table of n, a(n) for n = 1..1000</a>
%e Dec61=prime -> Hex61=Dec97=prime -> Hex97=Dec151=prime -> Hex151=Dec337=prime -> Hex337=Dec823=prime.
%t qhpQ[n_]:=AllTrue[Rest[NestList[FromDigits[IntegerDigits[#],16]&,n,4]], PrimeQ]; Select[Prime[Range[27000]],qhpQ] (* The program uses the AllTrue function from Mathematica version 10 *) (* _Harvey P. Dale_, Mar 13 2016 *)
%o (PARI) isok(p)= isprime(p) && isprime(p=hd(p)) && isprime(p=hd(p)) && isprime(p=hd(p)) && isprime(p=hd(p)); \\ _Michel Marcus_, Feb 09 2014
%Y Cf. A102489.
%Y Cf. A103144 (Hex-primes), A237438 (Double Hex-primes), A237439 (Triple Hex-primes), A237441 (Quintuple Hex-primes).
%K nonn,base
%O 1,1
%A _Andreas Boe_, Feb 07 2014
%E More terms from _Michel Marcus_, Feb 09 2014