Skip to content
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

[Merged by Bors] - feat: the n-th harmonic number is not an integer for n > 1. #7319

Closed
wants to merge 74 commits into from

Conversation

kodyvajjha
Copy link
Collaborator

The n-th Harmonic number is not an integer for n > 1. This proof uses 2-adic valuations.


This proof is of Theorem 1 in Keith Conrad's blurb. This proof is credited to Kürschák (1918). From this it follows that the 2-adic valuation of H_n tends to infinity as n does. We quickly run into open problems when similar questions are asked for odd primes p.

Open in Gitpod

Copy link
Collaborator

@Ruben-VandeVelde Ruben-VandeVelde left a comment

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Please don't be intimidated by the comments below, they're simple stylistic suggestions

Counterexamples/HarmonicNotInteger.lean Outdated Show resolved Hide resolved
Counterexamples/HarmonicNotInteger.lean Outdated Show resolved Hide resolved
Counterexamples/HarmonicNotInteger.lean Outdated Show resolved Hide resolved
Counterexamples/HarmonicNotInteger.lean Outdated Show resolved Hide resolved
Counterexamples/HarmonicNotInteger.lean Outdated Show resolved Hide resolved
Mathlib/NumberTheory/Padics/PadicVal.lean Outdated Show resolved Hide resolved
Mathlib/NumberTheory/Padics/PadicVal.lean Outdated Show resolved Hide resolved
Mathlib/NumberTheory/Padics/PadicVal.lean Outdated Show resolved Hide resolved
Mathlib/NumberTheory/Padics/PadicVal.lean Outdated Show resolved Hide resolved
Mathlib/NumberTheory/Padics/PadicVal.lean Outdated Show resolved Hide resolved
@jcommelin jcommelin added the awaiting-author A reviewer has asked the author a question or requested changes label Sep 22, 2023
@kodyvajjha kodyvajjha changed the title The n-th Harmonic number is not an integer for n > 1. feat: the n-th harmonic number is not an integer for n > 1. Sep 23, 2023
@kodyvajjha
Copy link
Collaborator Author

@Ruben-VandeVelde thank you for your comments, I've incorporated most of them and the build passes. @alexjbest suggested that we could move this material out of Counterexamples and into mathlib proper. I could do that as a follow up PR if that works.

Mathlib/NumberTheory/Padics/PadicVal.lean Outdated Show resolved Hide resolved
Mathlib/NumberTheory/Padics/PadicVal.lean Outdated Show resolved Hide resolved
Mathlib/NumberTheory/Padics/PadicVal.lean Outdated Show resolved Hide resolved
Mathlib/NumberTheory/Padics/PadicVal.lean Outdated Show resolved Hide resolved
Mathlib/NumberTheory/Padics/PadicVal.lean Outdated Show resolved Hide resolved
Mathlib/NumberTheory/Padics/PadicVal.lean Outdated Show resolved Hide resolved
Mathlib/NumberTheory/Padics/PadicVal.lean Outdated Show resolved Hide resolved
@kodyvajjha kodyvajjha added awaiting-review The author would like community review of the PR and removed awaiting-author A reviewer has asked the author a question or requested changes labels Sep 25, 2023
@kodyvajjha
Copy link
Collaborator Author

i think i've addressed most of the comments - just waiting now for the build to turn green, thanks everyone!

Mathlib/NumberTheory/Padics/PadicVal.lean Outdated Show resolved Hide resolved
Mathlib/NumberTheory/Padics/PadicVal.lean Outdated Show resolved Hide resolved
Mathlib/NumberTheory/Padics/Harmonic.lean Outdated Show resolved Hide resolved
kodyvajjha and others added 4 commits September 27, 2023 22:21
Co-authored-by: Thomas Browning <tb65536@users.noreply.github.com>
Co-authored-by: Thomas Browning <tb65536@users.noreply.github.com>
Co-authored-by: Thomas Browning <tb65536@users.noreply.github.com>
Copy link
Collaborator

@tb65536 tb65536 left a comment

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Looking very good. Maybe someone else can take one last look over?

Mathlib/Data/Finset/Basic.lean Outdated Show resolved Hide resolved
Mathlib/Data/Finset/Basic.lean Outdated Show resolved Hide resolved
Mathlib/NumberTheory/Padics/PadicNorm.lean Outdated Show resolved Hide resolved
Mathlib/NumberTheory/Padics/PadicVal.lean Outdated Show resolved Hide resolved
Mathlib/NumberTheory/Padics/PadicVal.lean Outdated Show resolved Hide resolved
kodyvajjha and others added 3 commits September 28, 2023 15:49
Co-authored-by: Thomas Browning <tb65536@users.noreply.github.com>
Co-authored-by: Thomas Browning <tb65536@users.noreply.github.com>
Co-authored-by: Thomas Browning <tb65536@users.noreply.github.com>
Copy link
Member

@alexjbest alexjbest left a comment

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

lgtm once those last two comments are taken care of

kodyvajjha and others added 2 commits September 28, 2023 17:48
Co-authored-by: Thomas Browning <tb65536@users.noreply.github.com>
@alexjbest
Copy link
Member

maintainer merge

@github-actions
Copy link

🚀 Pull request has been placed on the maintainer queue by alexjbest.

@alexjbest
Copy link
Member

Thanks for making all these changes @kodyvajjha, hopefully the next PR will be smoother :)

@kodyvajjha
Copy link
Collaborator Author

Hahaha hopefully! Thanks @alexjbest

Copy link
Member

@jcommelin jcommelin left a comment

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Thanks 🎉

bors merge

@leanprover-community-mathlib4-bot leanprover-community-mathlib4-bot added ready-to-merge This PR has been sent to bors. and removed awaiting-review The author would like community review of the PR labels Sep 29, 2023
bors bot pushed a commit that referenced this pull request Sep 29, 2023
The n-th Harmonic number is not an integer for n > 1. This proof uses 2-adic valuations.
@bors
Copy link

bors bot commented Sep 29, 2023

Pull request successfully merged into master.

Build succeeded!

The publicly hosted instance of bors-ng is deprecated and will go away soon.

If you want to self-host your own instance, instructions are here.
For more help, visit the forum.

If you want to switch to GitHub's built-in merge queue, visit their help page.

@bors bors bot changed the title feat: the n-th harmonic number is not an integer for n > 1. [Merged by Bors] - feat: the n-th harmonic number is not an integer for n > 1. Sep 29, 2023
@bors bors bot closed this Sep 29, 2023
@bors bors bot deleted the kody/harmonicnotinteger branch September 29, 2023 05:56
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment
Labels
ready-to-merge This PR has been sent to bors.
Projects
None yet
Development

Successfully merging this pull request may close these issues.

None yet

6 participants