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Primes of form a^2+b^2 such that a^4+b^4 and a^8+b^8 are primes.
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%I #13 May 13 2013 01:54:19

%S 2,5,17,1277,2129,3413,4157,4637,7481,7573,7717,14561,15233,19469,

%T 19889,20549,20693,20749,22721,23609,23869,24841,27701,29629,31153,

%U 35869,41081,42209,42577,44417,45233,46061,51613,51713,52069,53197,54493,55589,55921,56489

%N Primes of form a^2+b^2 such that a^4+b^4 and a^8+b^8 are primes.

%H Charles R Greathouse IV, <a href="/A182313/b182313.txt">Table of n, a(n) for n = 1..10000</a>

%o (PARI) list(lim)=my(v=List([2]),t);for(a=1,sqrt(lim),forstep(b=1+a%2, min(a,sqrt(lim-a^2)), 2, if(isprime(t=a^2+b^2) && isprime(a^4+b^4) && isprime(a^8+b^8), listput(v,t)))); vecsort(Vec(v)) \\ _Charles R Greathouse IV_, Apr 24 2012

%Y Subsequence of A182198.

%K nonn

%O 1,1

%A _Thomas Ordowski_, Apr 24 2012

%E a(4)-a(40) from _Charles R Greathouse IV_, Apr 24 2012