Ai–Guo–Freschi–Lo Ore-type conjecture for oriented Hamilton cycles

From papers

Let GG be an oriented graph, that is, a loopless directed graph with at most one edge between any two vertices. For a vertex, let its total degree be the number of incident edges, and let δ(G)\delta(G) be the minimum total degree. For an oriented cycle C=v1vv1C=v_1\ldots v_\ell v_1, let σ+(C)\sigma^+(C) and σ(C)\sigma^-(C) be the numbers of edges traversed in the forward and backward directions, respectively, and define

σmax(C)=max{σ+(C),σ(C)}.\sigma_{\max}(C)=\max\{\sigma^+(C),\sigma^-(C)\}.

For non-adjacent vertices x,yx,y, meaning that there is no edge between them, define

σ2(G)=min{d(x)+d(y)x,yV(G) and x,y are non-adjacent}.\sigma_2(G)=\min\{d(x)+d(y)\mid x,y\in V(G)\text{ and }x,y\text{ are non-adjacent}\}.

Ai–Guo–Freschi–Lo conjecture. Let GG be an oriented graph on n3n\geq 3 vertices. If σ2(G)n\sigma_2(G)\geq n, then GG contains a Hamilton cycle CC such that

σmax(C)σ2(G)2.\sigma_{\max}(C)\geq \frac{\sigma_2(G)}{2}.

This is an Ore-type extension of the oriented discrepancy analogue of Dirac's theorem. The supplied text says the problem was proposed as a conjecture by Ai et al.; the paper itself resolves the corresponding asymptotic result, but does not state that this exact conjecture has been solved.

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Primary source

Yufei Chang, Yangyang Cheng, Zhilan Wang, Shuo Wei and Jin Yan, “An Ore-type Theorem for Oriented Discrepancy of Hamilton Cycles”, arXiv:2603.18915 (2026).

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