Alex Chengyu Li · ErdősProblems.com #1212
What is claimed?
We prove that this graph contains an infinite simple path, answering Erdős Problem 1212 affirmatively. More precisely, for almost every slope in a fixed interval away from the diagonal, there is a ray with that limiting coordinate ratio.
Quoted from the source · Significance editor · 2026-09-08 §Abstract, p.1 · View source
Component dates
- Preprint
- 2026-09-07
- Exposition
- Not recorded
- Formalization
- 2026-09-07
Reader summary
- Claimed
- Alex Chengyu Li reports an infinite simple path in the composite-restricted visible lattice and an almost-everywhere limiting-direction result. The author selected release v1.0.1 for this private draft.
What has been checked?
Significance inspected the problem and claim pages, repository links, and pinned v1.0.1 version; resolved the tag to a commit; and computed the manuscript PDF SHA-256 from the raw file at that commit.
- Independent reruns
- 0
- Math assessments
- 0
- Written reviews
- 0
Problem link
ErdősProblems.com #1212 · open the original problem page
Author involvement
The author contributed a suggested review task. Private correspondence is not reproduced.
Start here · for reviewers
Main deduction
Compare Section 1's graph and path conditions with Problem 1212, Target.lean, and the literal endpoint in AlgebraicCorridorKernelAudit.lean.
Risk points
Check that the composite-coordinate restriction and unit adjacency agree across the problem, paper, and named Lean statements.
Check the passage from the injective infinite path to the original question's path going to infinity.
Useful background
Section 1 of the paper, the repository README, and the two named Lean files; familiarity with reading Lean statements.
Needs checking
List the statements and conditions compared and any specific discrepancy or remaining question within the author's bounded correspondence check.
- Suggest another focused check
Formalization handoff
A compact map for someone who wants to formalize this claim. It records preparation and open work, not a mathematical verdict.
- Target
- The graph and path conditions in Problem 1212, Target.lean, and the literal endpoint in AlgebraicCorridorKernelAudit.lean. Significance’s interpretation · Significance editor · 2026-09-08 §Private correspondence; message text withheld.
- System
- Lean 4 Quoted from the source · Significance editor · 2026-09-08 · View source
- Work state
- Artifact reported
- Code
- formalization repository · commit
400001f0847a…
Copy for sharing
Copy and paste this summary.
Alex Chengyu Li reports an infinite simple path in the composite-restricted visible lattice and an almost-everywhere limiting-direction result. The author selected release v1.0.1 for this private draft. Checked: Significance inspected the problem and claim pages, repository links, and pinned v1.0.1 version; resolved the tag to a commit; and computed the manuscript PDF SHA-256 from the raw file at that commit. Not checked: The mathematics has not been independently assessed. Significance has not reproduced the Lean build or established statement correspondence. The author-supplied correspondence task and independent verification remain open. As of 2026-09-08T14:30:26Z (freshness: current) Full record: https://hjyuh.github.io/significance/2026-alexchengyuli-erdos-1212/ Significance records evidence. It does not judge the mathematics.
- Scope
- This private draft concerns the author's claimed infinite path in the composite-restricted visible lattice and the author-selected v1.0.1 release. The optional monotonicity and bounded-turn strengthening is outside the reported scope. Statement correspondence and independent mathematical assessment remain open. Significance’s interpretation · Significance editor · 2026-09-08 · View source
- Source
- Infinite paths in the composite-restricted visible lattice
Evidence: 6 entries
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Source inspection
ev-source-inspectionPublic-source and version check only. This is not a mathematical review.
Significance inspected the public problem and proof-claim pages and their source links, located the pinned manuscript version, and computed its SHA-256 from the downloaded PDF bytes. The mathematics has not been independently assessed; the author-supplied task remains open.
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Source inspection
ev-ai-claim-disclosurePublic-source and version check only. This is not a mathematical review.
A full proof claimed by Alex Chengyu Li (using Proof Engine (doi.org/… doi.org/… with ChatGPT 5.6 and ChatGPT 6 Astra).
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Source inspection
ev-version-pinPublic-source and version check only. This is not a mathematical review.
The author-selected tag v1.0.1 resolves to commit 400001f0847a…. manuscript.url is the raw PDF at that commit; its SHA-256 is 2a31595c68dd…, computed from 283837 downloaded bytes at 2026-09-08T14:23:09Z. The claim page still names v1.0.0; the author's later message selects v1.0.1.
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Formal code published by the source
ev-formalization-reportedPublished by the source. Any independent rerun appears as a separate entry.
The specific Problem 1212 proof claim links this Lean repository as its formalization. The pinned v1.0.1 release was published on 2026-09-07 and includes the manuscript, Lean sources, and audit material. This records a published artifact, not an independent reproduction.
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Source inspection
ev-publication-datePublic-source and version check only. This is not a mathematical review.
The pinned v1.0.1 release containing this manuscript was published on 2026-09-07. This dates the pinned manuscript release, not its earliest circulation.
Limits of this record
- This record does not issue a whole-paper correctness judgement.
- Open invitations identify work not yet represented by a completed evidence entry.
- No independent reproduction or mathematical assessment is represented unless an evidence entry above says otherwise.