Problem detail · source-aware

North-East Lattice Paths with Few Collinear Vertices

partialconfidence 70%

VibeMathed reports this item as partial. VibeMath preserves that report as a source assertion and has not independently authored a plain-language mathematical explanation.

Precise statement

Let $A(k)$ be the largest possible number of moves in a north-east lattice path whose visited vertices contain no $k$ collinear points. Gerver (1979) and Gerver and Ramsey (1979) bounded $A(k)$ by $$\exp\left(\Omega\left(\log(k)^2\right)\right) \le A(k) \le \exp\left(O\left(k^4\right)\right),$$ and determining the true growth rate has been open since. Both bounds are improved to $$\exp\left(\Omega\left(k^{1/3}\right)\right) \le A(k) \le \exp\left(O\left(k^2\right)\right),$$ with the upper bound proved in the sharper form $\exp\left(\left(\tfrac{2}{e}+o(1)\right)(k-1)^2\right)$.

The source statement is reproduced for indexing with attribution. Mathematical correctness requires domain-expert or mechanical review. VibeMath has not independently audited statement fidelity, correctness, priority, or novelty.

What AI did

GPT-5.5 Pro

The acknowledgement in full: the author was assisted by GPT-5.5 Pro in preparing the paper, but "the main construction ideas, including the dyadic-interval random variables in the lower bound and the density-increment framework in the upper bound, were due to the author". AI tools checked computations, assisted with drafting, and improved the upper-bound constant by suggesting the use of the mediant of the relevant Farey fractions. That last contribution is traceable in the text: it lifts the density increment from $(1/8-o(1))(k-1)^{-2}$ to $(1/4-o(1))(k-1)^{-2}$, which is what produces the $2/e$ constant. So the model sharpened the constant inside the new upper bound rather than the exponent, which is the lower tier by this site's definition.

Provider: OpenAI · Prompt public: unknown · Independence: unknown

Verification boundary

unreviewed

Checked by this site on 17 August 2026 against the paper's LaTeX (arXiv:2607.02832, Korsky, 2 July 2026). The abstract matches this entry, and the acknowledgement is verbatim as the AI-role note now quotes it - including the sentence attributing the main construction ideas to the author, which the submission's quote had omitted. The model's named contribution was traced through the text to the density-increment step it actually improves. The prior bounds attribute correctly: Gerver, Pacific J. Math. 83 (1979) 349-355, and Gerver-Ramsey, same volume, 357-363. The proofs themselves - a dyadic slope-field random construction and a Farey-mediant density increment - were not checked here and need a discrete geometer. Unrefereed preprint, no independent review.

Correctness: unknown · statement fidelity: unaudited · peer review: none

Timeline

  1. North-East Lattice Paths with Few Collinear Vertices (arXiv)

    Both bounds move, and the gap stays enormous: the lower bound rises from $\exp(\Omega(\log^2 k))$ to $\exp(\Omega(k^{1/3}))$ and the upper falls from $\exp(O(k^4))$ to $\exp(O(k^2))$, so $A(k)$ is still undetermined between an exponent of $k^{1/3}$ and one of $k^2$. The paper's own closing discussion argues its lower-bound construction is near the limit of the method and that beating it needs additional randomness, a sharper line-counting step, or a different model entirely.

Known method families

argument (source-reported)

Source-reported tools: argument.

Independent: unknown · difference confidence: 0

What remains uncertain

VibeMath has not independently audited the mathematical statement, proof, or novelty claim.

  • VibeMath has not independently verified the mathematical claim.
  • AI-attempt independence and training-data exposure are unknown unless explicitly documented.
  • VibeMath has not independently audited the mathematical statement, proof, or novelty claim.