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.

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

Offset

1,1

Comments

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?

Links

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

Example

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.

Crossrefs

Cf. A000040, A060084.

Sequence in context: A056720 A100850 A309607 * A114370 A114725 A136340

Adjacent sequences: A060082 A060083 A060084 * A060086 A060087 A060088

Keyword

nonn

Author

Marc LeBrun, Feb 23 2001

Extensions

Corrected by Jud McCranie, Sep 03 2002

Status

approved