Proving there is no smallest rational number greater than 1
51649
prove there is no smallest positive rational number
1117
Is there a bijection between $(0,1)$ and $\mathbb{R}$ that preserves rationality?
134963
Proving a non-prime (composite) number $> 1$ has a divisor $d \leq\sqrt q$
138446
Proving that there exists an irrational number in between any given real numbers
31522
Proving $f$ has at least one zero inside unit disk
5529
Proving that $x$ is irrational if $x-\lfloor x \rfloor + \frac1x - \left\lfloor \frac1x \right\rfloor = 1$
150037
Finding the simplest rational in a closed interval
19954
Perfect set without rational numbers
111490
Proof that every number has at least one prime factor
67161
No maximum(minimum) of rationals whose square is lesser(greater) than $2$.
56464
Proving the irrationality of $e^n$
107448
proving that there is no solution for $n$ in positive integers except $n = 1$ for $2^n = nk + 1$
75012
Additive group of rationals has no minimal generating set
2705
How many roots have modulus less than $1$?
66210
Prove that $z^n + 1/{z^n}$ is a rational number
134377
The minimum number of digits after the floating-point, which uniquely identify every irrational square root
142008
Find all natural numbers $n$ such that ${(n+1)}^{1/2}-{(n-1)}^{1/2}$ is rational