If $n>4$ and is composite, then $n$ divides $(n-1)!$.
9319
If $n\ne 4$ is composite, then $n$ divides $(n-1)!$.
8609
Prove by induction that $n!>2^n$
114393
If $a$ is divisible by $4$, then there exist int $b$ and $c$ such that $a = b^2 - c^2$
100558
Prove that for any even positive integer $n$, $n^2-1 \mid 2^{n!}-1$
91197
Proving $n! \ge 2^{n-1 }$for all $n\ge1 $by mathematical Induction
7894
Does it follow that $(n!)^n$ divide $(n^2)!$
26514
Prove that if $n$ is a composite, then $2^n-1$ is composite.
34374
Simplifying factorials: $\frac{(n-1)!}{(n-2)!}$
144622
Proof: If no prime less than or equal to $\sqrt{n}$ divides $n$, then $n$ is a prime
33866
Show that $n$ does not divide $2^n - 1$ where $n$ is an integer greater than $1$?
1507
The product of $n$ consecutive integers is divisible by $n$ factorial
153123
Proving by induction $4^n  0$
80216
Prove if $n \in \mathbb N$, then $\frac{1}{2!}+\cdots+\frac{n}{(n+1)!}=1-\frac{1}{(n+1)!}$
123033
Showing a number $n$ is prime if $(n-2)! \equiv 1 \pmod n$
22367
How do I prove that for every positive integer $n$, there exist $n$ consecutive positive integers, each of which is composite?
123117
Is it possible to find $n-1$ consecutive composite integers
73102
Given the factors of $N$, is there a method for computing the factors of $N-1$ or $N+1$?