-
Notifications
You must be signed in to change notification settings - Fork 209
feat(ErdosProblems): 794 #1739
New issue
Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.
By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.
Already on GitHub? Sign in to your account
base: main
Are you sure you want to change the base?
feat(ErdosProblems): 794 #1739
Conversation
formalize Erdős google-deepmind#794 (disproved)
|
Thanks for your pull request! It looks like this may be your first contribution to a Google open source project. Before we can look at your pull request, you'll need to sign a Contributor License Agreement (CLA). View this failed invocation of the CLA check for more information. For the most up to date status, view the checks section at the bottom of the pull request. |
| /-- Harris's counterexample has exactly 28 edges. -/ | ||
| @[category test, AMS 5] | ||
| theorem harrisCounterexample_card : HarrisCounterexample.card = 28 := by native_decide | ||
|
|
||
| /-- Harris's counterexample is 3-uniform. -/ | ||
| @[category test, AMS 5] | ||
| theorem harrisCounterexample_is3Uniform : Is3Uniform HarrisCounterexample := by | ||
| unfold Is3Uniform | ||
| native_decide |
There was a problem hiding this comment.
Choose a reason for hiding this comment
The reason will be displayed to describe this comment to others. Learn more.
Can these be closed with decide or decide +kernel ?
There was a problem hiding this comment.
Choose a reason for hiding this comment
The reason will be displayed to describe this comment to others. Learn more.
Tried decide / decide +kernel, but it hit maxRecDepth during lake build.
There was a problem hiding this comment.
Choose a reason for hiding this comment
The reason will be displayed to describe this comment to others. Learn more.
Done, ran this morning and avoided maxRecDepth
| ∃ (S : Finset α) (_ : S ∈ Finset.univ.powersetCard k), | ||
| (H.filter (fun e => e ⊆ S)).card ≥ m |
There was a problem hiding this comment.
Choose a reason for hiding this comment
The reason will be displayed to describe this comment to others. Learn more.
| ∃ (S : Finset α) (_ : S ∈ Finset.univ.powersetCard k), | |
| (H.filter (fun e => e ⊆ S)).card ≥ m | |
| ∃ S : Finset α, #S = k \and #{e \in H | e ⊆ S} ≥ m |
You will need open Finset first
| -- `answer(False)` is `False`, so this is equivalent to `¬ Statement`. | ||
| simp only [false_iff] |
There was a problem hiding this comment.
Choose a reason for hiding this comment
The reason will be displayed to describe this comment to others. Learn more.
| -- `answer(False)` is `False`, so this is equivalent to `¬ Statement`. | |
| simp only [false_iff] | |
| simp? |
and see what it comes up with
Adds a formalization of Erdős Problem 794 (disproved; see erdosproblems.com/794). Hope this is a good fit for the repository’s “short counterexample / not a lengthy proof” guideline but I'm happy to adjust if you’d prefer a different level of abstraction. Completed with the assistance of Harmonic's Aristotle and Claude Opus 4.5.