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%I #5 Jun 30 2015 13:17:41
%S 5,17,37,13,101,29,197,257,401,97,577,677,157,53,41,89,1297,1601,353,
%T 149,73,461,61,541,2917,3137,673,277,769,241,4357,5477,109,1217,173,
%U 269,7057,569,1549,8101,1693,8837,709,113,137,2081,373,661,2333,12101,193
%N Primitive prime factors of the sequence 4k^2 + 1 in the order that they are found.
%C a(n) mod 8 = 1 or 5, all primes p mod 8 = 1 or 5 can be found on this sequence.
%H Bernhard Helmes, <a href="http://www.devalco.de/quadr_Sieb_4x%5E2+1.php">Prime sieving on the polynomial f(n)=4n^2+1</a>.
%K nonn
%O 1,1
%A Bernhard Helmes (pi(AT)devalco.de), Oct 16 2008