What was already known
Erdős #146 proposed an n^(3/2)-scale upper growth rate for the specified two-degenerate bipartite class.
AI involvement
OpenAI attributes the construction and Lean formalization to Astra. Humans selected the problem and prepared the manuscript.
OpenAI’s original disclosure assigns the argument and subsequent Lean formalization to Astra; human manuscript preparation is separately credited.
- Supporting source (github.com) — TwoDegenerateGraphs.twoDegenerateExtremalCounterexample
Importance
Resolves the named extremal-graph question by counterexample.
Limitations
The result concerns a graph meeting the chapter’s degree conditions. Human reviewers requested an expanded optimization in Lemma 5.1; the Lean certificate is source-reported.
Technical verification
The project reports a complete Lean certificate for the stated formal theorem. Human assessments have narrower scope; semantic matching and any manuscript gaps remain separately noted.
Independent checking
chapter-specific mathematical review of the published argument, with the limited coverage summarized in the audit. Table 1; Chapter 10 discussion
- Checker
- Chapter 10 human reviewers in the Sienicki et al. review corpus
- Scope
- both main Chapter 10 results, with a missing displayed optimization in Lemma 5.1
- Basis
- Reported by the linked checker
Formal checking
Lean 4.32.0 formal certificate in CompactnessAndDegeneracy.lean; comparator target for TwoDegenerateGraphs.twoDegenerateExtremalCounterexample; manifest reports zero sorry and only standard axioms. main_results entry TwoDegenerateGraphs.twoDegenerateExtremalCounterexample; status and axioms
- Checker
- OpenAI ten-proofs project, Lean kernel and Comparator configuration
- Scope
- two-degenerate bipartite extremal counterexample with exponent above 3/2
- Basis
- Reported by the linked checker
Checking a formal statement does not establish that it matches the original problem.
Human understanding
The two Chapter 10 assessments and manuscript explain the layered/sampled graph construction and forbidden-subgraph argument; the remaining requested optimization is an expository calculation.
Correction and publication history
Resolves the named extremal-graph question by counterexample.
Read this published revision