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JDH
  • Member for 11 years, 11 months
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151 votes
Accepted

Are the "proofs by contradiction" weaker than other proofs?

131 votes

How many sides does a circle have?

112 votes

What are the issues in modern set theory?

100 votes
Accepted

In classical logic, why is $(p\Rightarrow q)$ True if $p$ is False and $q$ is True?

94 votes
Accepted

difference between maximal element and greatest element

92 votes

Is infinity an odd or even number?

63 votes
Accepted

When is the closure of an open ball equal to the closed ball?

52 votes

Does it ever make sense NOT to go to the most prestigious graduate school you can get into?

49 votes

Lebesgue Measure of the Graph of a Function

40 votes
Accepted

Prove there are no hidden messages in Pi

39 votes
Accepted

Is there such a thing as a countable set with an uncountable subset?

38 votes

Help me put these enormous numbers in order: googol, googol-plex-bang, googol-stack and so on

37 votes
Accepted

Vitali-type set with given outer measure

34 votes

Formal proof that $\mathbb{R}^{2}\setminus (\mathbb{Q}\times \mathbb{Q}) \subset \mathbb{R}^{2}$ is connected.

31 votes

Perfect set without rationals

31 votes
Accepted

Density of halting Turing machines

31 votes

Can a circle truly exist?

31 votes

Is there a definitive guide to speaking mathematics?

30 votes

Why is it that Complex Numbers are algebraically closed?

29 votes

What is the order-type of the set of natural numbers, when written in alphabetical order?

28 votes
Accepted

Bijection between $2^{\mathbb R}$ and $\mathbb{ R ^ R}$

28 votes

False beliefs about Lebesgue measure on $\mathbb{R}$

27 votes

Irrationality proofs not by contradiction

26 votes

Does a Person Need a Mathematics Degree in order to Publish in a Mathematics jounal?

26 votes
Accepted

Infinite number of mistakes in a proof

26 votes

Comparing countable models of ZFC

25 votes

Surreal and ordinal numbers

25 votes

Example of different topologies with same convergent sequences

23 votes
Accepted

Is there an absolute notion of the infinite?

23 votes
Accepted

What interesting open mathematical problems could be solved if we could perform a "supertask" and what couldn't?

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