Factorials and their perfect squares
8034
Can $n!$ be a perfect square when $n$ is an integer greater than $1$?
112867
Find all digits $a,b$ such that the number $\overline{aabb}$ is a perfect square
21108
Perfect squares and modularly congruency in mod 5
112644
The product of two numbers that can be written as the sum of two squares
140433
The number of ways of writing an integer as a sum of two squares
153647
Elementary number theory and quadratic
31970
Alternating sum of squares of binomial coefficients
130499
How can $p^{q+1}+q^{p+1}$ be a perfect square?
48787
A number is a perfect square if and only if it has odd number of positive divisors
5692
Proving that there is a perfect square between $n$ and $2n$
58589
On the factorial equations $A! B! =C!$ and $A!B!C! = D!$
146305
Simplify sum of factorials with mathematical induction
121469
Proof of observations on natural numbers being expressed as differences of squares.
67968
When is $2^n -7$ a perfect square?
65581
$m$ is a perfect square iff $m$ has an odd number of divisors?
78593
Prove that the product of four consecutive positive integers plus one is a perfect square
17306
To find all $n$ such that $(n-1)!+1$ is a perfect power of $n$