%I #20 Mar 03 2018 18:25:43
%S 5,3,7,17,11,31,13,43,127,257,19,73,41,23,89,683,241,2731,8191,29,113,
%T 151,331,65537,43691,131071,37,109,174763,524287,61681,337,5419,397,
%U 2113,47,178481,2796203,97,673,251,601,1801,4051,53,157,1613,87211,262657,15790321,59,233,1103,2089,3033169,61,1321,715827883,2147483647
%N List of primitive prime divisors of the numbers (4^n-1)/3 (A002450) in their order of occurrence.
%C Read A002450 term-by-term, factorize each term, write down any primes not seen before in increasing order for each term.
%H James R. Buddenhagen, <a href="/A129735/a129735.txt">List giving n followed by primitive prime divisors of (4^n-1)/3 for n=1..70</a>
%H G. Everest, S. Stevens, D. Tamsett and T. Ward, <a href="http://www.uea.ac.uk/~h008/research/primes.pdf">Primes Generated by Recurrence Sequences</a>, 2006.
%H G. Everest et al., <a href="http://www.jstor.org/stable/27642221">Primes generated by recurrence sequences</a>, Amer. Math. Monthly, 114 (No. 5, 2007), 417-431.
%H Wikipedia, <a href="https://en.wikipedia.org/wiki/Zsigmondy%27s_theorem">Zsigmondy's theorem</a>
%H K. Zsigmondy, <a href="https://doi.org/10.1007%2FBF01692444">Zur Theorie der Potenzreste</a>, Monatsh. Math., 3 (1892), 265-284.
%e The primes grouped according to successive terms of A002450, courtesy of _James R. Buddenhagen_:
%e [5], [3, 7], [17], [11, 31], [13], [43, 127], [257], [19, 73], [41], [23, 89, 683], [241], [2731, 8191], [29, 113], [151, 331], [65537], [43691, 131071], [37, 109], [174763, 524287], [61681], [337, 5419], [397, 2113], [47, 178481, 2796203], [97, 673], [251, 601, 1801, 4051], [53, 157, 1613], [87211, 262657], [15790321], [59, 233, 1103, 2089, 3033169], [61, 1321], [715827883, 2147483647], ...
%Y Cf. A002450, A129733.
%K nonn
%O 1,1
%A _N. J. A. Sloane_, May 13 2007
%E Order of terms corrected by _James R. Buddenhagen_, Jul 23 2015