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%I #9 Sep 13 2017 03:13:48
%S 17,19,31,41,59,61,67,71,89,101,103,107,109,127,137,139,149,157,163,
%T 167,193,199,227,229,241,257,269,271,293,311,313,331,347,349,373,379,
%U 389,401,409,421,433,449,479,503,509,521,523,541,563,599,607,613,631,647
%N Primes p such that gpf(lpf(2^p - 1) - 1) > p.
%C Complement of A291691 w.r.t. primes.
%C Are there infinitely many such primes? - _Thomas Ordowski_, Sep 12 2017
%e For p=17, we have gpf(lpf(2^p - 1) - 1) = 257 which is > 17, so 17 is a term.
%o (PARI) lista(nn) = forprime(p=2, nn, if (vecmax(factor(vecmin(factor(2^p-1)[, 1])-1)[, 1]) > p, print1(p, ", ")););
%Y Cf. A001348, A291691, A292238.
%K nonn
%O 1,1
%A _Michel Marcus_, Sep 12 2017
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