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 A213052 Increasing sequence of primes p such that all of 2,3,5,...,prime(n) are primitive roots mod p. 7
 3, 5, 53, 173, 293, 2477, 9173, 22613, 27653, 61613, 74093, 92333, 170957, 360293, 679733, 847997, 2004917, 69009533, 76553573, 138473837, 237536213, 777133013, 883597853, 1728061733, 2050312613, 5534091197, 9447241877, 49107823133, 65315700413 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS a(32) > 10^12. - Dana Jacobsen, Jul 13 2018 LINKS Dana Jacobsen, Table of n, a(n) for n = 1..31 PROG (PARI) N=10^10; default(primelimit, N); A=2; { forprime (p=3, N,     q = 1;     forprime (a=2, A,         if ( znorder(Mod(a, p)) != p-1,  q=0; break() );     );     if ( q, A=nextprime(A+1); print1(p, ", ") ); ); } (Perl) use Math::Prime::Util ":all"; my(\$N, \$A, \$p, \$a, @P7) = (10**11, 2); forprimes { \$p=\$_;   if (   is_primitive_root(2, \$p)       && (\$A < 3 || is_primitive_root(3, \$p))       && (\$A < 5 || is_primitive_root(5, \$p))       && (\$A < 7 || vecall { is_primitive_root(\$_, \$p) } @P7)     ) {       print "\$p\n";       \$A = next_prime(\$A);       push @P7, \$A if \$A >= 7;     } } 3, \$N; # Dana Jacobsen, Jul 11 2018 CROSSREFS Sequence in context: A260226 A101149 A056260 * A260223 A260225 A020462 Adjacent sequences:  A213049 A213050 A213051 * A213053 A213054 A213055 KEYWORD nonn,hard AUTHOR Joerg Arndt, Jun 03 2012 EXTENSIONS a(20)-a(27) from Joerg Arndt, Apr 10 2016 a(28)-a(29) from Dana Jacobsen, Jul 11 2018 STATUS approved

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Last modified August 9 01:35 EDT 2020. Contains 336310 sequences. (Running on oeis4.)