Erdős Problem #74: locally almost bipartite graphs of infinite chromatic number

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VibeMathed record: Erdős Problem #74: locally almost bipartite graphs of infinite chromatic number evidence for this event

Epoch AI, Announcing FrontierMath Erdős (1 September 2026) evidence for this event

Astra proves that there exists a divergent function $$f:\mathbb N\to\mathbb N,\qquad f(n)\to\infty,$$ such that no graph $G$ of infinite chromatic number can satisfy $$d_{\mathrm{bip}}(H)\le f(n)$$ for every finite $n$-vertex subgraph $H\subseteq G$, where $d_{\mathrm{bip}}(H)$ is the minimum number of edges that must be deleted to make $H$ bipartite. In fact, every included resolution proves the stronger statement that graphs satisfying the constructed local bound are 3-colorable. The formal challenge advertises only the weaker conclusion that their chromatic number must be finite. parent of this event

Challenge.lean: the compared statement evidence for this event

This event attributed to Tom Adamczewski

Solution.lean and the Lean development evidence for this event

Erdős Problem #74: locally almost bipartite graphs of infinite chromatic number evidence for this event

This event attributed to GPT-6 Astra (pre-release)

erdosproblems.com/74: status and Thomas Bloom's proof exposition evidence for this event

Erdős Problem #74: locally almost bipartite graphs of infinite chromatic number parent of this event