Tagged Questions

0
votes
0answers
66 views

Beatty proof adaptation ?

If $m$ and $n$ are coprime integers, prove that each of these $m+n-2$ fractions: $$\frac{m+n}{m},\frac{2(m+n)}{m},\frac{3(m+n)}{m},...,\frac{(m-1)(m+n)}{m},$$ $$\frac{m+n}{n},\frac …
0
votes
1answer
146 views

prod and sig in COQ

Hello, Apparently in COQ the type prod (with one constructor pair) corresponds to cartesian product and the type sig (with one constructor exist) to dependent sum but how is descr …
37
votes
9answers
3k views

How do they verify a verifier of formalized proofs?

In an unrelated thread Sam Nead intrigued me by mentioning a formalized proof of the Jordan curve theorem. I then found that there are at least two, made on two different systems. …
1
vote
1answer
330 views

How to interpret conflicting formal proofs about “a mod 0 = ? ”

The proof assistants Coq and Isabelle give conflicting formal proofs about $a \mod 0 \qquad \forall a \in \mathbb{Z}$. According to Coq $$ a \mod 0 = 0$$ and Isabelle proves $$ a …
1
vote
0answers
292 views

Can someone help me in a proof about Kolakoski sequence? [closed]

Hello everyone. I am not a mathematician but recently I was thinking about one of Kimberling's questions he posted here: http://faculty.evansville.edu/ck6/integer/index.html , i.e …
20
votes
4answers
3k views

Why is it so difficult to write complete (computer verifiable) proofs?

For example I have read that is agony to give a complete proof of the Jordan curve theorem. Since all statements are meant to be justified by the postulates, where does the difficu …
4
votes
1answer
672 views

categorifying induction in homotopy type theory

In trying to understand homotopy type theory, I stumbled upon the following silly question, which is likely to be trivial for the experts. Let $B=\sqcup_{n\in\Bbb N} BS_n$, which …
1
vote
0answers
584 views

Why should I trust Coq when assumption-free proof of False in Coq exists? [closed]

Damien Pous announced code for assumption-free proof of False in Coq which means inconsistency in Coq (without using exploits, lol). Damien is critical of "fully certified decisio …
22
votes
5answers
2k views

Proof assistants for mathematics

This question is related to (maybe even the same in intent as) Question 1017, but none of the answers seem to address what I'm looking for. There are a lot of resources available …
11
votes
7answers
1k views

Intro to automatic theorem proving / logical foundations?

Is there any web-based course or materials about logic / automatic theorem proving? (I checked MIT's OpenCourseWare and I only found a vaguely related AI course)
5
votes
6answers
2k views

Is there any proof assistant based on first-order logic?

I'm looking for a proof assistant in order to write formal proofs about basic facts of set theory, such as: $a\subseteq a$ $(a,b)=(c,d)\leftrightarrow a=c\land b=d$ Natural ded …
3
votes
1answer
797 views

Proving inequalities over algebraic structures

I've been looking at proof techniques in formal systems like Coq and Agda recently, and encountered the newring tactic described here for proving equalities over arbitrary (semi)ri …
1
vote
2answers
725 views

What is a semigroup or, what do I do with that associativity proof?

Mathematically, I know what a semigroup is: It is a set S along with an associative binary operation $* : S \times S \rightarrow S$. So far, so good. From a computational perspe …
5
votes
1answer
888 views

Is there a known way to formalise notion that certain theorems are essential ones?

Suppose You ask a question beginning from "Why some structure is..." or "Why some object has property..." and several answers arises. Which criteria do You use to qualify which an …
5
votes
3answers
579 views

Proof formalization

I read some time ago some papers about proof formalization. Typically, I began whith this one, from Lamport. Are there more recent works in this field ?