User Jay

28 votes

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How can I prove that one of $n$, $n+2$, and $n+4$ must be divisible by three, for any $n\in\mathbb{N}$

answered Oct 11, 2013 at 14:07

14 votes

Is there any conjecture that has been proved to be solvable/provable but whose direct solution/proof is not yet known?

answered Aug 12, 2018 at 22:27

10 votes

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Complete lattices and sublattices – which requirement is more stringent?

answered May 16, 2011 at 0:28

9 votes

Showing that a set X with a trivial topology is not metrizable

answered Apr 20, 2011 at 1:01

8 votes

Why is 'abuse of notation' tolerated?

answered Dec 25, 2012 at 17:26

7 votes

How to understand why $x^0 = 1$, where $x$ is any real number?

answered Nov 15, 2012 at 23:25

7 votes

Is the box topology good for anything?

answered May 5, 2011 at 2:15

7 votes

Is there a Non-prime Number that is Divisible only by Numbers Greater than its Square Root?

answered Jun 19, 2011 at 19:01

6 votes

Show: $\mathbb{C}=\overline{\mathbb{C}\setminus\left\{0\right\}}$

answered Jul 17, 2013 at 14:38

6 votes

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Subset Relation: Is the subset relation a partial order?

answered Oct 6, 2014 at 15:05

6 votes

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Which combination of Peano axioms shows that $0\neq 1?$

answered Sep 21, 2022 at 11:47

5 votes

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What underlies formal logic (or math, generally)?

answered Dec 18, 2013 at 14:18

5 votes

Is Scrabble's method of determining turn order fair?

answered Aug 29, 2017 at 17:05

5 votes

Example of a conjecture/theorem which required an entirely new idea to prove

answered Dec 16, 2012 at 22:48

5 votes

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Does anyone know of any good ways to get good at algebra without as much"grind" as doing hundreds of questions a night

answered May 15, 2011 at 1:04

5 votes

Possibility of getting odd pair socks

answered Jun 25, 2011 at 11:58

5 votes

Bad Fraction Reduction That Actually Works

answered Jul 6, 2011 at 1:36

5 votes

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If all the vectors of a basis of a vector space are contained in another space, is the first space a subspace of the second?

answered Oct 18, 2011 at 22:39

5 votes

How it is posible that $\omega$-inconsistency does not lead to inconsistency

answered Feb 18, 2012 at 13:59

4 votes

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Why are convex sets assumed / defined to be subsets of vector spaces (and not of more general spaces)?

answered Oct 5, 2011 at 23:16

4 votes

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Books and Papers that have treatment of properties like Idempotence and related operations

answered Apr 22, 2011 at 22:48

4 votes

Concept of set without concept of member?

answered Aug 13, 2013 at 0:51

4 votes

Direct proof set theory.

answered Sep 19, 2013 at 23:13

4 votes

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If G is a finite group and $x \in G$, there is an integer n $\geq 1$ such that $x^n = e$

answered Apr 17, 2014 at 23:28

4 votes

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Theorems which are proven by proving the existence of a formal proof without knowing the formal proof

answered Apr 29, 2014 at 22:36

4 votes

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Can you make a Sine wave with a straight edge and compass?

answered Oct 9, 2021 at 18:56

3 votes

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How many automorphisms are there for $ \langle \omega , < \rangle $?

answered Nov 15, 2022 at 14:18

3 votes

Is the set of proposition symbols necessarily a countable set?

answered Dec 11, 2018 at 13:14

3 votes

Upper limit of summation index lower than lower limit?

answered Apr 25, 2011 at 21:14

3 votes

Two posets and a function

answered Jul 7, 2011 at 20:57

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125 Answers

How can I prove that one of $n$, $n+2$, and $n+4$ must be divisible by three, for any $n\in\mathbb{N}$

Is there any conjecture that has been proved to be solvable/provable but whose direct solution/proof is not yet known?

Complete lattices and sublattices – which requirement is more stringent?

Showing that a set X with a trivial topology is not metrizable

Why is 'abuse of notation' tolerated?

How to understand why $x^0 = 1$, where $x$ is any real number?

Is the box topology good for anything?

Is there a Non-prime Number that is Divisible only by Numbers Greater than its Square Root?

Show: $\mathbb{C}=\overline{\mathbb{C}\setminus\left\{0\right\}}$

Subset Relation: Is the subset relation a partial order?

Which combination of Peano axioms shows that $0\neq 1?$

What underlies formal logic (or math, generally)?

Is Scrabble's method of determining turn order fair?

Example of a conjecture/theorem which required an entirely new idea to prove

Does anyone know of any good ways to get good at algebra without as much"grind" as doing hundreds of questions a night

Possibility of getting odd pair socks

Bad Fraction Reduction That Actually Works

If all the vectors of a basis of a vector space are contained in another space, is the first space a subspace of the second?

How it is posible that $\omega$-inconsistency does not lead to inconsistency

Why are convex sets assumed / defined to be subsets of vector spaces (and not of more general spaces)?

Books and Papers that have treatment of properties like Idempotence and related operations

Concept of set without concept of member?

Direct proof set theory.

If G is a finite group and $x \in G$, there is an integer n $\geq 1$ such that $x^n = e$

Theorems which are proven by proving the existence of a formal proof without knowing the formal proof

Can you make a Sine wave with a straight edge and compass?

How many automorphisms are there for $ \langle \omega , < \rangle $?

Is the set of proposition symbols necessarily a countable set?

Upper limit of summation index lower than lower limit?

Two posets and a function