User graydad - Mathematics Stack Exchange

graydad

Member for 9 years, 4 months
Last seen more than 1 year ago

9 Questions

Score Activity Newest Views

8 votes

2 answers

2k views

Mary Ellen Rudin's proof that all metric space are paracompact

asked Sep 3, 2014 at 17:06

6 votes

2 answers

220 views

Prove that $\mathbb{R}^{n}-A$ with the standard topology is connected where $n \geq 2$ and $A \subset \mathbb{R}^{n}$ is countable.

asked Jul 31, 2014 at 0:40

4 votes

5 answers

1k views

Uniqueness of radix representation of integers in base 3

asked Jan 5, 2015 at 16:04

3 votes

5 answers

904 views

Show that two different representations to the base $k$ represent two different integers

asked Jan 13, 2015 at 0:13

3 votes

2 answers

525 views

Exact value of $\sum_{n=1}^\infty \frac{1}{n(n+k)(n+l)}$ for $k \in \Bbb{N}-\{0\}$ and $l \in \Bbb{N}-\{0,k\}$

asked Nov 16, 2014 at 18:52

2 votes

1 answer

1k views

An alternative proof of the Tietze Extension Theorem(s)

asked Nov 19, 2014 at 21:07

2 votes

3 answers

772 views

The set of elements that do not escape the tent map is a Cantor Set

asked Sep 3, 2014 at 17:42

2 votes

2 answers

142 views

A stupid puzzle, but a reward of pizza

asked Aug 5, 2015 at 14:19

1 vote

5 answers

102 views

Concise induction step for proving $\sum_{i=1}^n i^3 = \left( \sum_{i=1}^ni\right)^2$

asked Dec 4, 2014 at 15:57