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%I #21 Sep 08 2022 08:46:05
%S 2,3,7,11,23,41,47,53,59,61,71,73,83,97,101,113,127,139,149,157,173,
%T 179,181,191,197,199,211,223,229,239,257,263,271,277,281,307,331,337,
%U 347,359,373,379,383,389,397,409,419,433,439,443,463,467,479,499,509
%N Primes that divide some term of A006720.
%C The density of primes in this sequence is 11/21.
%C If p divides A006720(n) for some n, then the smallest such n is <= (1/2)*((sqrt(p)+1)^2+3).
%H Jeremy Rouse, <a href="/A227199/b227199.txt">Table of n, a(n) for n = 1..10000</a>
%H R. Jones and J. Rouse, <a href="http://arxiv.org/abs/0706.2384">Galois Theory of Iterated Endomorphisms</a>, Proceedings of the London Mathematical Society, 100, no. 3 (2010), 763-794.
%e 11 is in the sequence because 11 divides A006720(10) = 1529.
%o (Magma) [ n : n in [2..500] | IsPrime(n) and (n ne 37) and (Order(EllipticCurve([GF(n)!0,0,1,-1,0])![0,0,1]) mod 2 eq 1) ];
%K easy,nonn
%O 1,1
%A _Jeremy Rouse_, Sep 18 2013