VibeMathedMath problems solved by AI

The Lonely Runner Conjecture for Nine and Ten Runners

The Lonely Runner Conjecture of Wills and Cusick states that among k+1k+1 runners at distinct constant speeds on a unit circle, each runner is at some time at distance at least 1/(k+1)1/(k+1) from all others. Following Rosenfeld's computer-assisted proof for 8 runners, the paper refines his approach with a sieve and proves the cases of 9 and 10 runners.

Result
Proved(see note)
Status
Partial result
AI contribution
AI-assisted
Method
Computation
Field
Diophantine approximation
Posed by
Jörg M. Wills; independently Thomas W. Cusick
Year posed
1967
Years open
58y
Solved
2025-11-27
Model
GPT-5
Vendor
OpenAI
Collaborators
Tanupat Trakulthongchai
Verification
Unreviewed
Publication
Preprint
Significance
30 / 100
Disclosed cost
Wikipedia
No dedicated article

What was actually shown

Settles 9 and 10 runners only; the general conjecture remains open.

What the AI did

"We employed OpenAI GPT-5 to assist with code generation, especially in low-level optimization" of the C++ verification that constitutes the proof; code and result receipts are public.

Verification

A computer-assisted proof in the Rosenfeld tradition; the code and receipts are public but no independent rerun or review has appeared.

Source

arXiv

Discussion