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Primes which have more primitive roots than any smaller prime.
5

%I #13 Sep 07 2022 09:04:32

%S 2,5,11,17,23,29,41,47,53,59,83,107,137,149,167,173,179,227,257,263,

%T 269,293,317,347,359,383,389,467,479,503,509,557,563,587,653,719,773,

%U 797,809,839,857,863,887,929,977,983,1019,1049,1097,1109,1187,1229

%N Primes which have more primitive roots than any smaller prime.

%H Jeppe Stig Nielsen, <a href="/A103203/b103203.txt">Table of n, a(n) for n = 1..100000</a>

%o (PARI) my(record=0, r); forprime(p=2, 1500, r=eulerphi(p-1); if(r>record, record=r; print1(p,", "))) \\ _Jeppe Stig Nielsen_, Oct 18 2019

%Y Cf. A103521, A121519, A008330.

%K nonn

%O 1,1

%A _Don Reble_, Mar 19 2005