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A060085 a(n) gives least prime for which the n-th prime is the least prime which is not a primitive root of a(n) (see A060084), or 0 if the n-th prime never occurs in A060084. 3
2, 3, 5, 53, 773, 173, 293, 2477, 22613, 9173, 61613, 280013, 92333, 74093, 170957, 360293, 679733, 36300197, 2004917, 69009533, 138473837, 237536213, 777133013, 883597853, 2411100677, 3519879677, 2050312613, 19570048973, 80471253917, 65315700413, 1728061733 (list; graph; refs; listen; history; text; internal format)



Note that these are the smallest primes such that exactly the first n primes are primitive roots.

a(n) gives the prime corresponding to the first appearance of the n-th prime in A060084. The n-th prime is the least prime not a primitive root of a(n) and for all primes p < a(n) the n-th prime (i.e. A000040(n)) is either a primitive root of p, or else there is a smaller prime q which is not a primitive root of a(n). Question: does a value exist for all primes?


Don Reble, Table of n, a(n) for n = 1..40


a(4)=23 because the first occurrence of 7 in A060084 is at n=9 and the 9th prime, A000040(9)=23. That is, a(4)=23 since the 4th prime, A000040(4), is 7 and 23 is the smallest prime p for which 7 is the least prime that is not a primitive root of p.


Cf. A000040, A060084.

Sequence in context: A322947 A056720 A100850 * A114370 A114725 A136340

Adjacent sequences:  A060082 A060083 A060084 * A060086 A060087 A060088




Marc LeBrun, Feb 23 2001


Corrected by Jud McCranie, Sep 03 2002



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Last modified May 19 14:36 EDT 2019. Contains 323395 sequences. (Running on oeis4.)