OpenAI reports the strong thin spanning-tree bound

There is a universal C such that every finite loopless k-edge-connected multigraph on at least two vertices has a spanning tree meeting each nontrivial cut in at most C/k times the number of original cut edges.

Sources for this record

What was already known

Goddyn’s thin-tree conjecture asked for arbitrarily thin trees at sufficiently high connectivity; the strong version asks for the optimal order C/k, which the manuscript says remained open.

AI involvement AI-led

OpenAI credits itself as manuscript author and states that its internal frontier model produced the results in this release. Individual human input is not detailed enough to establish task-only autonomy.

OpenAI is named as author on the manuscript, and its release attributes the results to an internal frontier model. The individual human input is not detailed enough to establish autonomy.

Importance Major

Resolves the quantitative strong thin-tree conjecture at the necessary 1/k scale.

Limitations

The selected first-paper claim is existential and does not specify C or an algorithm; a separate companion formalization describes a deterministic algorithm.

Technical verification Formal (Lean 4)

OpenAI reports a Lean proof matching the selected claim.

Formal checking

The pinned OpenAI Lean scope note identifies this selected claim.

Checker
OpenAI-reported Lean 4 / Comparator
Scope
There is a universal C such that every finite loopless k-edge-connected multigraph on at least two vertices has a spanning tree meeting each nontrivial cut in at most C/k times the number of original cut edges.
Basis
Reported by the linked checker
Evidence source

Checking a formal statement does not establish that it matches the original problem.

Human understanding Few

Few is the default when evidence for a higher level is insufficient. No named person is documented as explaining the central argument for this assessed contribution.

Correction and publication history

2026-10-18 · publication

Primary manuscript, attribution, prior-work, and scoped checking review for non-notifying local inclusion.

Read this published revision