Positive integers x,y,z such that $x!+y!=z!$
86935
Finding all the numbers that fit $x! + y! = z!$
86413
Show that $\frac{(m+n-1)!}{m!n!}$ is an integer where m and n are positive integers and gcd(m,n)=1
86285
Given positive integers $ x , y$ and that $3x^2 + x = 4y^2 +y$ Prove that $x-y$ is a perfect square
45914
Proving that $n!≤((n+1)/2)^n$ by induction
129163
Showing that every positive integer can be represented in this form
22073
Prove by induction that $n^2<n!$
31295
$x+y\sqrt{2}$ infimum ($x,y\in \mathbb{Z}$)
40343
Solutions of $p!q! = r!$
49209
Prove $(x+y)(y+z)(x+z)≤\frac8{27}(x+y+z)^3$
42516
If every $x\in X$ is uniquely $x=y+z$ then $\|z\|+\|y\|\leq C\|x\|$
149489
30 positive integers
100558
Prove that for any even positive integer $n$, $n^2-1 \mid 2^{n!}-1$
90806
Find all positive integers $n$ such that $n$ is divisible by all the positive integers less than or equal to $\sqrt{n}$
41383
Prove that $(x+y+z)^2(yz+zx+xy)^2 \leq 3(y^2+yz+z^2)(z^2+zx+x^2)(x^2+xy+y^2)$
98443
Find positive integers such that $2n^3 + 5|n^4 +n+1$
56624
Prove that $0!+1! + 2! + 3! + ..... + n!$ $\neq$ $p^\text{r}$, where $n \geqslant 3$ and $n$, $p$ and $r$ are three integers
83496
Math contest integer triplet problem: $x + y + z + xy + yz + xz = xyz − 1$