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Vincenzo Librandi, Table of n, a(n) for n = 1..1000
Index entries for primes by primitive root
pr=23; Select[Prime[Range], MultiplicativeOrder[pr, # ] == #-1 &]
(PARI) is(n)=isprime(n) && n!=23 && znorder(Mod(23, n))==n-1 \\ Charles R Greathouse IV, Sep 28 2015
Sequence in context: A076706 A243441 A256426 * A235630 A235636 A103074
Adjacent sequences: A019347 A019348 A019349 * A019351 A019352 A019353
David W. Wilson