Why $1$ isn't a prime?
48587
Why is $1$ not a prime number?
75685
Prove that there is prime number and natural so $n\times q$ digits are $1$.
2802
If $2^n+1$ is prime, why must $n$ be a power of $2$?
65511
Proving the following false: $f(x)=2x+1$ produces a prime number if and only if x is prime
24444
Prove that $371\cdots 1$ is not prime
134963
Proving a non-prime (composite) number $> 1$ has a divisor $d \leq\sqrt q$
51382
Proving that either $2^n-1 $ or $ 2^n+1$ is not prime
43939
Show that $3^{2n+1}-4^{n+1}+6^n$ is never prime for natural n except 1.
29572
Proof that $2^n-1$ does not always generate primes when primes are plugged in for $n$?
66851
If $p,q$ are primes $(pq,a)=1$ and $p-1|q-1$ then prove $a^{q-1}\equiv 1\pmod{pq}$
65826
Find a prime number $p$ and an integer $b<p$ such that $p$ divides $b^{p−1}−1$.
123544
Show that $n = 3^{100} + 2$ is not a prime number.
71110
Show that we cannot have a prime triplet of the form $p$, $p + 2$, $p + 4$ for $p >3$
7415
why only square root approach to check number is prime
23932
Why do repunit primes have only a prime number of consecutive $1$s?
153862
A question about a primitive root mod $p=2^{2^k}+1$, where $p$ is prime.
63356
Can $x^{n}-1$ be prime if $x$ is not a power of $2$ and $n$ is odd?