login
This site is supported by donations to The OEIS Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
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)
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: A322947 A056720 A100850 * 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

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

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