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_Charles R Greathouse IV_, , <a href="/A047936/b047936.txt">Table of n, a(n) for n = 1..10000</a>
_Charles R Greathouse IV, _, <a href="/A047936/b047936.txt">Table of n, a(n) for n = 1..10000</a>
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lst={}; Do[p=Prime[n]; pr=PrimitiveRoot[p]; If[pr>1&&!PrimeQ[pr], AppendTo[lst, p]], {n, 7!}]; lst [From _(* _Vladimir Joseph Stephan Orlovsky_, Oct 24 2009] *)
Select[Prime[Range[500]], !PrimeQ[PrimitiveRoot[#]]&] (* From _Harvey P. Dale, _, Oct 24 2011 *)
\\ _Charles R Greathouse _ IV, Oct 24 2011
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Primes for which whose smallest positive primitive root (A001918) is not prime.
Subsequence of A222717 = primes whose smallest positive quadratic nonresidue is not a primitive root. (Proof. If p is not in A222717, then the smallest positive quadratic nonresidue of p is a primitive root g. Since the smallest positive quadratic nonresidue is always a prime, g is prime. But since all primitive roots are quadratic nonresidues, g is the smallest positive primitive root of p. Hence p is not in A047936.) - Jonathan Sondow, Mar 13 2013.
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lst={}; Do[p=Prime[n]; pr=PrimitiveRoot[p]; If[pr>1&&!PrimeQ[pr], AppendTo[lst, p]], {n, 7!}]; lst [From _Vladimir Joseph Stephan Orlovsky (4vladimir(AT)gmail.com), _, Oct 24 2009]