A Variation of "rational is dense in $\Bbb R$"
117132
Rationals of the form $\frac{p}{q}$ where $p,q$ are primes in $[a,b]$
68490
For $x\in\mathbb R\setminus\mathbb Q$, the set $\{nx-\lfloor nx\rfloor: n\in \mathbb{N}\}$ is dense on $[0,1)$
78082
Dense subset of two Banach spaces also dense in the intersection
78915
Density of the set $S=\{m/2^n| n\in\mathbb{N}, m\in\mathbb{Z}\}$ on $\mathbb{R}$?
17461
Show that a set is dense in $[-1,1]$
135574
Help proving the primitive roots of unity are dense in the unit circle.
25795
Density of $\mathbb{Q}^n$ in $\mathbb{R}^n$
67259
Can we prove that a bounded closed subset of $\mathbb R^n$ is compact without Axiom of Choice?
92571
Sets with no asymptotical density over $\mathbb N$
95294
Dense subset of $C[0,1]$ which preserves rationals
50880
Expressing $\Bbb N$ as an infinite union of disjoint infinite subsets.
135441
When is $\mathbb{Z}[\alpha]$ dense in $\mathbb{C}$?
61226
Group Structure on $\Bbb R$
137030
Why are there more Irrationals than Rationals given the density of $Q$ in $R$?
129205
A question about uncountable, dense sets in R
26256
Characterizing Dense Subgroups of the Reals
67244
Why is $L^1(\mathbb{R}^n) \cap L^2(\mathbb{R}^n)$ dense in $ L^2(\mathbb{R}^n)$?