List Erdős–Neumann-Lara conjecture

From papers

Let GG be a graph. Its list chromatic number χ(G)\chi_{\ell}(G) is the least integer rr such that every assignment of lists of rr colours to the vertices admits a proper list colouring. For an orientation DD of GG, define its list dichromatic number χ(D)\vec\chi_{\ell}(D) analogously, using list colourings in which every colour class induces an acyclic digraph, and let

χ(G)=maxDχ(D),\vec\chi_{\ell}(G)=\max_D\vec\chi_{\ell}(D),

where the maximum is over all orientations DD of GG.

List Erdős–Neumann-Lara conjecture. For every integer kk there is an integer f(k)f(k) such that, for every graph GG, χ(G)f(k)\chi_{\ell}(G)\geq f(k) implies χ(G)k\vec\chi_{\ell}(G)\geq k.

The paper states that it proves this list version of the Erdős–Neumann-Lara conjecture, so the claim is resolved by the source's results.

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Sources & referencesView supporting material

Primary source

Ararat Harutyunyan, Lucas Picasarri-Arrieta and Gil Puig i Surroca, “On the list version of a conjecture of Erdős and Neumann-Lara”, arXiv:2603.01020 (2026).

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