User Lucas K.

12 votes

Writing "Semi-Formal" Proofs

answered Feb 14, 2011 at 22:51

10 votes

Undecidable easy arithmetical statement

answered Nov 7, 2017 at 22:12

9 votes

What are the most attractive Turing undecidable problems in mathematics?

answered May 24, 2010 at 19:59

7 votes

Ask for recommendations for textbook on mathematical logic

answered Apr 15, 2011 at 18:25

5 votes

Are there any very hard unknots?

answered Jan 27, 2011 at 22:50

5 votes

What are the most attractive Turing undecidable problems in mathematics?

answered May 25, 2010 at 20:33

5 votes

Goodstein's theorem without transfinite induction

answered Jun 24, 2013 at 17:45

5 votes

Examples of common false beliefs in mathematics

answered Sep 5, 2015 at 22:05

4 votes

What is Realistic Mathematics?

answered Aug 10, 2010 at 22:18

4 votes

What's your favorite equation, formula, identity or inequality?

answered Jun 2, 2010 at 19:47

4 votes

Are any natural examples of Gödel speed-up known?

answered May 18, 2011 at 11:11

3 votes

Would Euler's proofs get published in a modern math Journal, especially considering his treatment of the Infinite?

answered May 13, 2010 at 12:00

2 votes

What is the reverse mathematics of first-order logic and propositional logic?

answered May 16, 2010 at 11:03

2 votes

Can we color Z^+ with n colors such that a, 2a, ..., na all have different colors for all a?

answered May 30, 2010 at 10:43

2 votes

Arguments against large cardinals

answered Oct 29, 2010 at 20:04

2 votes

What can be done with computability logic that previous logic systems can't?

answered Jun 17, 2013 at 22:42

1 vote

How to prove Con(PA) in ZFC?

answered Dec 22, 2010 at 18:26

1 vote

Accepted

Can invariant of transitive reflexive closure in FOL+PA always been proven?

answered Dec 30, 2012 at 14:25

1 vote

Accepted

Measuring how "heavily linked" a node is in a graph

answered May 9, 2010 at 22:05

0 votes

A decision problem in graph coloring

answered Jul 9, 2010 at 23:43

0 votes

"Simpler" statements equivalent to Con(PA) or Con(ZFC)?

answered Apr 28, 2011 at 19:41

0 votes

Remove unnecessary dependencies in a task graph?

answered May 18, 2010 at 22:26

-9 votes

What would you want to see at the Museum of Mathematics?

answered Dec 26, 2010 at 16:40

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23 Answers

Writing "Semi-Formal" Proofs

Undecidable easy arithmetical statement

What are the most attractive Turing undecidable problems in mathematics?

Ask for recommendations for textbook on mathematical logic

Are there any very hard unknots?

What are the most attractive Turing undecidable problems in mathematics?

Goodstein's theorem without transfinite induction

Examples of common false beliefs in mathematics

What is Realistic Mathematics?

What's your favorite equation, formula, identity or inequality?

Are any natural examples of Gödel speed-up known?

Would Euler's proofs get published in a modern math Journal, especially considering his treatment of the Infinite?

What is the reverse mathematics of first-order logic and propositional logic?

Can we color Z^+ with n colors such that a, 2a, ..., na all have different colors for all a?

Arguments against large cardinals

What can be done with computability logic that previous logic systems can't?

How to prove Con(PA) in ZFC?

Can invariant of transitive reflexive closure in FOL+PA always been proven?

Measuring how "heavily linked" a node is in a graph

A decision problem in graph coloring

"Simpler" statements equivalent to Con(PA) or Con(ZFC)?

Remove unnecessary dependencies in a task graph?

What would you want to see at the Museum of Mathematics?