All Questions
8 questions
14
votes
1
answer
565
views
Legendary extra parameters to simplify a counting problem
I am reading Proofs and Confirmations, the history behind the alternating sign matrix conjecture, regarding counting $n \times n$ alternating sign matrices. In the introduction, it is written that ...
16
votes
2
answers
1k
views
Examples of problems where considering "discrete analogues" has provided insight or led to a solution of the original problem
The Kakeya conjecture posits that any Kakeya set in $\mathbb{R}^n$ has dimension $n$.
A discrete (finitized?) version of this problem is the Finite Field Kakeya conjecture, which was proved by Dvir ...
31
votes
11
answers
2k
views
Combinatorial databases
At one point, I remember being excited by seeing the website Encyclopedia of Combinatorial Structures as an extension of Sloane's Online Integer Sequence Database site. Unfortunately, the site (ECS) ...
0
votes
6
answers
436
views
Equivalence relations not associated with a group
This is a vague question; so vague that I wonder if anyone will get it. Many, perhaps most, equivalence relations that are regularly used in mathematics correspond to the orbits of some group action ...
20
votes
4
answers
13k
views
Two questions about combinatorics journals
Hello,
I have two questions regarding combinatorics journals. I hope that this is the right place for such questions.
Which combinatorics/DM journals would you consider as the "top tier"?
I tried to ...
6
votes
4
answers
1k
views
fourier analytic proofs
While searching through Mathoverflow, I found out a fourier analytic proof of the Isoperimetric Inequality.Also, by google search I found a fourier analytic proof of Quadratic Reciprocity theorem.I ...
4
votes
3
answers
286
views
Medium-Sized Calculations and Organization
This is not a math question as much as a process question. For the first time in my (very short) career, I find myself doing one of those messy calculations, where each 'line' of the calculation can ...
- 63
16
votes
11
answers
15k
views
Different ways of proving that two sets are equal
I'm not sure if this is a soft question, or should be community wiki.
I was explaining to a student how to prove that two sets were equal using what I called the 'oldest trick in the book': to show ...