Prime numbers of form $a^n-1$.
59036
If $a^{n}-1$ is prime then $a=2$ and $n$ is prime?
63356
Can $x^{n}-1$ be prime if $x$ is not a power of $2$ and $n$ is odd?
45461
Is there a prime which is the form of $10^n + 1$ except $2, 11, 101$?
98468
Are there infinitely many primes of the form $n!+1$?
48691
Product of all prime numbers upto some prime $p$
113763
Let $p$,$\ q$ be prime numbers and $n\in \mathbb{N}$ such that $p \nmid n-1$. If $p \mid n^q-1$, then $q \mid p-1$.
82482
Proving an infinite number of primes of the form 6n+1
42885
Fermat primes relation to $2^n+1$
75685
Prove that there is prime number and natural so $n\times q$ digits are $1$.
64782
How to prove if $n$ is prime and $n | a^2$ then $n | a$?
50781
$(n+1)$th prime $p_{n+1}$ less than or equal to $p_1p_2\dots p_n+1$
11440
When is the number $11111\cdots1$ a prime number?
18634
Combinations of sets raised to the power of a prime modulus: $\binom{p^{\alpha}-1}k \equiv (-1)^k \pmod p$
112120
Find all primes of the form $2^{2^n} + 5$ for a nonnegative integer n
66851
If $p,q$ are primes $(pq,a)=1$ and $p-1|q-1$ then prove $a^{q-1}\equiv 1\pmod{pq}$
31184
Sums of powers below a prime
151036
arithmetic progression of primes