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A262264 Primes that are less than the square of their least positive primitive root. 0
3, 7, 23, 191, 409 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Alternatively, primes such that the least positive primitive root is greater than the square root of p.

Next term is greater than 10^9.

REFERENCES

References and links at A001918.

LINKS

Table of n, a(n) for n=1..5.

EXAMPLE

The least primitive root of 23 is 5; 5^2 is greater than 23, so 23 is in the sequence.

The least primitive root of 409 is 21; 21^2 = 441 is greater than 409, so 409 is in the sequence.

41 is not in the sequence because its least primitive root is 6, and 6^2 < 41.

MATHEMATICA

Select[Prime[Range[1000]], PrimitiveRoot[#]^2 > # &]

PROG

(PARI) /* the following assumes that znprimroot() returns the smallest primitive root */

forprime(p=2, 10^9, my(g=znprimroot(p)); if(lift(g)^2>p, print1(p, ", "))); \\ Joerg Arndt, Sep 17 2015

CROSSREFS

Cf. A001918 (least positive primitive root of n-th prime).

Sequence in context: A048721 A113824 A121883 * A060235 A090188 A001773

Adjacent sequences:  A262261 A262262 A262263 * A262265 A262266 A262267

KEYWORD

nonn,more

AUTHOR

Dale Taylor, Sep 17 2015

STATUS

approved

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Last modified August 21 05:37 EDT 2019. Contains 326162 sequences. (Running on oeis4.)