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Thomas Andrews

Cambridge, MA

thomasoandrews.com

Age: 47

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97
175 votes
23 answers

Examples of apparent patterns that eventually fail

big-list examples-counterexamples Apr 10 at 3:04 Douglas B. Staple
math.stackexchange.com

18
36 votes
5 answers

Solutions to $\binom{n}{5} = 2 \binom{m}{5}$

probability combinatorics binomial-coefficients diophantine-equations Apr 19 at 2:27 Kundor
math.stackexchange.com

23
34 votes
4 answers

Algebra: Best mental images

abstract-algebra group-theory ring-theory intuition visualization Apr 10 at 10:50 user1729
math.stackexchange.com

9
15 votes
1 answer

For which categories we can solve $\text{Aut}(X) \cong G$ for every group $G$?

group-theory category-theory big-list Jul 4 '12 at 7:52 Martin Brandenburg
math.stackexchange.com

6
11 votes
3 answers

Quantum mechanics for mathematicians

soft-question reference-request physics Sep 6 '11 at 23:29 r.g.
math.stackexchange.com

4
11 votes
4 answers

product of six consecutive integers being a perfect square

number-theory elementary-number-theory Jun 30 '12 at 9:32 Marc van Leeuwen
math.stackexchange.com

4
10 votes
3 answers

Problem about subsets of $\{1, 2,\dots,n\}$

combinatorics elementary-set-theory Mar 20 at 21:18 Sean Eberhard
math.stackexchange.com

5
9 votes
2 answers

Group theory intricate problem

group-theory contest-math Jun 27 '11 at 19:13 AlbertH
math.stackexchange.com

4
9 votes
1 answer

Information captured by differential forms

real-analysis multivariable-calculus intuition differential-forms Apr 17 '12 at 18:27 oen
math.stackexchange.com

5
9 votes
0 answers

How much do idempotent ultrafilters generate in terms of semigroups?

abstract-algebra general-topology semigroups filters Apr 20 at 22:24 Feanor
math.stackexchange.com

1
8 votes
1 answer

Möbius function from random number sequence

matrices elementary-number-theory recurrence-relations May 9 at 17:39 azimut
math.stackexchange.com

1
6 votes
1 answer

How does Tree(3) grow to get so big? Need laymen explanation.

graph-theory Mar 4 at 5:19 Deedlit
math.stackexchange.com

2
6 votes
1 answer

generalization of the Jordan curve theorem

algebraic-topology Jun 26 '11 at 17:56 gary
math.stackexchange.com

2
5 votes
2 answers

Is this quotient ring $\mathbb{C}[z_{ij}]/\ker\phi$ integrally closed?

algebraic-geometry commutative-algebra Nov 9 '12 at 19:48 YACP
math.stackexchange.com

2
4 votes
0 answers

There are $n$ horses. At a time only $k$ horse can run in the single race. How many minimum races are required to find the top $m$ fastest horses?

combinatorics Jan 19 at 13:12 Parth
math.stackexchange.com

5
3 votes
1 answer

$ \frac{1}{3a^2+1}+\frac{1}{3b^2+1}+\frac{1}{3c^2+1}+\frac{1}{3d^2+1} \geq \frac{16}{7}$

homework inequality Jan 3 at 18:33 Thomas Andrews
math.stackexchange.com

2
3 votes
0 answers

Number Theoretic Game

number-theory combinatorial-game-theory Aug 7 '12 at 20:11 user37333
math.stackexchange.com

3
3 votes
2 answers

Finding solutions to $(4x^2+1)(4y^2+1) = (4z^2+1)$

diophantine-equations Jun 26 '12 at 15:24 Tito Piezas III
math.stackexchange.com

2
2 votes
1 answer

Where to locate methods used by multiple Rails controllers & restricting access to the base controller

ruby-on-rails ruby mvc inheritance 2 days ago tybro0103
stackoverflow.com

3
1 vote
1 answer

Sum of prime powers equal to a prime power

elementary-number-theory Sep 7 '12 at 3:47 Gerry Myerson
math.stackexchange.com