OFFSET
1,1
COMMENTS
It is possible, although rather unlikely, that any primes congruent to 3 (mod 4) will appear in A213052.
a(19) > 10^11.
EXAMPLE
a(2) = 19 since 19 is the smallest prime (congruent to 3 (mod 4)) such that the first two primes (2 and 3) are primitive roots.
MATHEMATICA
max=0; Do[n=Prime@i; If[Mod[n, 4]==3, k=1; While[MultiplicativeOrder[Prime@k, n]==n-1, k++]; If[k-1>max, Print@n; max++]], {i, 10^6}] (* Giorgos Kalogeropoulos, Dec 17 2021 *)
PROG
(PARI)
N=10^10;
default(primelimit, N);
A=2;
{ forprime (p=3, N,
if (p%4==3,
q = 1;
forprime (a=2, A,
if ( znorder(Mod(a, p)) != p-1, q=0; break() );
);
if ( q, A=nextprime(A+1); print1(p, ", ") );
);
); }
CROSSREFS
KEYWORD
nonn,more
AUTHOR
Paul Vanderveen, Dec 15 2021
EXTENSIONS
a(19) from Daniel Suteu, Dec 20 2021
STATUS
approved