OpenAI reports elementary positivity of chromatic quasisymmetric functions

For every natural unit interval graph, its chromatic quasisymmetric function has nonnegative coefficients in the elementary basis over ℕ[q].

Sources for this record

What was already known

Shareshian and Wachs proved symmetry for this graph class and conjectured elementary positivity. Earlier reductions and special-case results did not establish it for every natural unit interval graph.

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 elementary-positivity part of the Shareshian–Wachs conjecture.

Limitations

The result does not assert elementary unimodality or the full Stanley–Stembridge conjecture beyond the stated graph class.

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
For every natural unit interval graph, its chromatic quasisymmetric function has nonnegative coefficients in the elementary basis over ℕ[q].
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