34,266 reputation
9108243
bio website blog.plover.com
location Philadelphia, USA
age
visits member for 2 years, 10 months
seen 5 hours ago

I am Mark Dominus, an amateur.

I have a blog that often carries articles about mathematics.

You can email me at mjd@plover.com.


1d
answered Scores of six soccer matches
1d
answered How many pairs of two distinct integers chosen from the set {1, 2, 3, …, 101} have a sum that is even?
1d
answered What does “removing a point” have to do with homeomorphisms?
1d
answered Why can't a direct proof be made backwards?
2d
answered What is the “fastest” increasing function that's useful in some area of math?
2d
answered Showing $(a,b) \sim (c,d)$ iff $a+d=b+c$ is transitive on $\mathbb{N}$
Dec
15
answered (Non?)-uniqueness of sums of squares
Dec
14
answered Silly Question on Excluded Middle
Dec
14
answered Train overtake time
Dec
13
answered Let $p \in \lbrace2,3,4,…\rbrace$. Suppose that for all $x,y \in \mathbb{Z}$, if $p \mid xy$, then $p \mid x \vee p \mid y$. Show that $p$ is prime.
Dec
12
answered Find all subgroups of group
Dec
11
answered Why do we focus so much in math on functions (as a subclass of relations)?
Dec
10
answered When was contemporary logical notation established
Dec
9
answered A question about infinities and pots of paint
Dec
9
answered Can you select random entry from unknown number of entries?
Dec
8
answered what is the generalization of this problem
Dec
5
answered Showing there is no natural number between two consecutive natural numbers
Dec
5
answered Definition: Equipollent
Dec
5
answered What is a simple example of an unprovable statement?
Dec
5
answered What is a simple example of an unprovable statement?