%I #8 Sep 21 2012 02:44:51
%S 12101,13553,30493,32429,44771,66067,103577,128987,180533,182711,
%T 187793,201829,242243,257489,264749,299113,314359,330331,337349,
%U 341947,356467,371471,431729,442619,475289,484243,505781,513767,540871,558053,564103,573299,581527,582011,586367,593869,596047,630169
%N Primes p such that x^11 = 2 has a solution mod p, but x^(11^2) = 2 has no solution mod p.
%o (PARI) forprime(p=2,550000,x=0; while(x<p&&x^11%p!=2%p,x++); if(x<p,y=0; while(y<p&&y^(11^2)%p!=2%p,y++); if(y==p,print1(p,","))))
%o (PARI)
%o N=10^6; default(primelimit,N);
%o ok(p, r, k1, k2)={
%o if ( Mod(r,p)^((p-1)/gcd(k1,p-1))!=1, return(0) );
%o if ( Mod(r,p)^((p-1)/gcd(k2,p-1))==1, return(0) );
%o return(1);
%o }
%o forprime(p=2,N, if (ok(p,2,11,11^2),print1(p,", ")));
%o /* _Joerg Arndt_, Sep 21 2012 */
%Y Cf. A049543, A059667, A070179 - A070186, A070188.
%K nonn
%O 1,1
%A _Klaus Brockhaus_, Apr 29 2002