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user132181
  • Member for 10 years, 2 months
  • Last seen more than 8 years ago
31 votes
1 answer
2k views

What axioms does ZF have, exactly?

19 votes
5 answers
2k views

Why study cardinals, ordinals and the like?

18 votes
3 answers
14k views

What's "the most right" symbol to use for "defined to be equal to"?

13 votes
5 answers
791 views

When can ZFC be said to have been "born"?

12 votes
2 answers
912 views

Ordinals - motivation and rigor at the same time

10 votes
5 answers
4k views

Precise meaning of "extension"?

8 votes
1 answer
188 views

Why are models in logic called models?

8 votes
2 answers
537 views

Is $e$ (Euler's number) involved in some geometric figure in any way?

8 votes
2 answers
2k views

Modern book on Gödel's incompleteness theorems in all technical details

7 votes
5 answers
2k views

How to make sense out of the $\epsilon-\delta$ definition of a limit? [duplicate]

6 votes
3 answers
172 views

Is there such a thing as the number of axioms?

6 votes
4 answers
3k views

Why is a sphere in an $n $-dimensional space called $(n-1) $-sphere?

5 votes
3 answers
281 views

Trivial proof in ZFC

5 votes
2 answers
281 views

If $\pi $ is a normal number, is $\tau $ one?

5 votes
1 answer
1k views

Why are power sets called power sets?

4 votes
2 answers
2k views

Does the arithmetic mean minimize the sum of absolute values of deviations? [duplicate]

4 votes
1 answer
77 views

Do only discs, sectors of discs, annuli, sectors of annuli and parallelograms have this property?

4 votes
2 answers
654 views

Definition of an $n$-tuple agreeing with the Kuratowski's definition of an ordered pair

4 votes
4 answers
2k views

Is $0 $ radians an acute angle?

3 votes
4 answers
241 views

If $\pi $ is normal, can it be used as a random number generator?

3 votes
1 answer
122 views

Difference between $\mathrm {d} x$ and $\delta x $

3 votes
1 answer
147 views

Confusion with Bolyai-Gerwien theorem

3 votes
1 answer
695 views

What's this number called and what are its properties?

3 votes
3 answers
131 views

What is wrong with the proof of this incorrect formula for the probability of $A\cap B$?

3 votes
0 answers
216 views

Asperger's and math [closed]

3 votes
3 answers
250 views

Truth values in formal systems

2 votes
1 answer
167 views

Justification for ordinal arithmetic at limit ordinals

2 votes
1 answer
179 views

Infinitely many nonequivalent unprovable statements in ZFC because of Gödel's incompleteness theorem?

2 votes
1 answer
101 views

Limits and nonstandard analysis - is my intuition correct?

2 votes
2 answers
629 views

Are Gödel's incompleteness theorems really about primitive recursive functions?