Erdős Problem a Daythe open tracker

Erdős Problem #740

OPENdatabase updated 2025-08-31

No proof or disproof is known, and it isn't known whether a finite computation could settle it.

What the community database records, not our verdict. erdosproblems.com no longer shows statuses (why).

A graph avoids odd cycles of length \(\leq r\) if it contains no odd cycles of length at most \(r\).

Let \(\mathfrak{m}\) be an infinite cardinal and \(G\) be a graph with chromatic number \(\mathfrak{m}\). Let \(r\geq 1\). Must \(G\) contain a subgraph of chromatic number \(\mathfrak{m}\) which does not contain any odd cycle of length \(\leq r\)?
Statement as formalized in Formal Conjectures (Google DeepMind, Apache-2.0) · their label: research open. The authoritative wording is on erdosproblems.com/740.
Prizenone
Topicsgraph theory, chromatic number
Statement in LeanFormal Conjectures
Solution in Leanno
Original pageerdosproblems.com/740
EARLY RUN BY THIS SITE · JUL 26, 2026

Literature map plus several open cases — no resolution.

NO PROGRESS