Primes $p$ in which $3$ is a primitive root modulo $p$
128575
Elementary proof that $3$ is a primitive root of a Fermat prime?
100255
If a prime divides the hypotenuse of a primitive Pythagorean triple, then $p \equiv 1$ (mod 4)
17919
For every prime of the form $2^{4n}+1$, 7 is a primitive root.
38727
Modular Exponentiation and Primes
64453
Prove if $(a,p)=1$, then $\{a,2a,3a,...,pa\}$ is a complete residue system modulo $p$.
46803
Proof that there are infinitely many primes congruent to 3 modulo 4
90273
Primitive roots of the unity in $\mathbb C$
134916
When g and -g are both primitive roots
104484
Prove that $r$ is a primitive root modulo $p$ if and only if $r^{(p−1)/q}\not\equiv 1\pmod{p}$
73515
Primes Number Theory
117516
Prime trios of the form $p$,$p+2$,$p+4$
78342
When is $\phi(n)$ a prime number?
85287
Prove that, for $p > 3$, $(\frac 3p) = 1$ when $p \equiv 1,11 \pmod{12}$ and $(\frac 3p) = -1$ when $p \equiv 5,7 \pmod{12}$
41312
Question on primitive roots of unity
100450
Prove that 3 is a primitive root of $7^k$ for all $k \ge 1$
87101
Irreducible but not prime in $K[X,Y]/(X^2-Y^3)$
146512
Prove that for every prime number $p>3$, $4p^2+1$ can be written as the sum of three square numbers