Can any body give me a reference of the result about primitive root mod p for a class of prime number p.
The result that I am looking for is something along this line:


$2$ is a primitive root mod $p$ for all prime $p$ of the form $p=4q+1$ where $q$ is also a prime.


Thanks in advance.



Reference of primitive root mod p
Take a look at "A criterion on primitive roots modulo p" by H.Park, J.Park, D.Kim.
There is a collection of various criteria including the above for small primes to appear as primitive roots. I hope it helps, or are you looking for something more general?


