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A070185 Primes p such that x^9 = 2 has a solution mod p, but x^(9^2) = 2 has no solution mod p. 3
3943, 5347, 11287, 12853, 14149, 17659, 20143, 21061, 21277, 23059, 23599, 25759, 26407, 26731, 29863, 32833, 33751, 35803, 37747, 38287, 39367, 39799, 46441, 47737, 47791, 54919, 57781, 59887, 61291, 62047, 63127, 65557, 68311, 71443, 73063, 75169, 78301, 79273, 82351, 84457, 84673, 86077, 88129, 90289 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..44.

PROG

(PARI) forprime(p=2, 72000, x=0; while(x<p&&x^9%p!=2%p, x++); if(x<p, y=0; while(y<p&&y^(9^2)%p!=2%p, y++); if(y==p, print1(p, ", "))))

(PARI)

N=10^6;  default(primelimit, N);

ok(p, r, k1, k2)={

    if (  Mod(r, p)^((p-1)/gcd(k1, p-1))!=1, return(0) );

    if (  Mod(r, p)^((p-1)/gcd(k2, p-1))==1, return(0) );

    return(1);

}

forprime(p=2, N, if (ok(p, 2, 9, 9^2), print1(p, ", ")));

/* Joerg Arndt, Sep 21 2012 */

CROSSREFS

Cf. A049596, A059667, A070179 - A070184, A070186 - A070188.

Cf. A059354.

Sequence in context: A162859 A115929 A346135 * A059354 A059666 A230707

Adjacent sequences:  A070182 A070183 A070184 * A070186 A070187 A070188

KEYWORD

nonn

AUTHOR

Klaus Brockhaus, Apr 29 2002

STATUS

approved

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Last modified October 22 01:48 EDT 2021. Contains 348160 sequences. (Running on oeis4.)