Corpus ID: 218516612

# Proof of Halin's normal spanning tree conjecture

@article{Pitz2020ProofOH,
title={Proof of Halin's normal spanning tree conjecture},
author={Max Pitz},
journal={arXiv: Combinatorics},
year={2020}
}
• Max Pitz
• Published 6 May 2020
• Mathematics
• arXiv: Combinatorics
Halin conjectured 20 years ago that a graph has a normal spanning tree if and only if every minor of it has countable colouring number. We prove Halin's conjecture. This implies a forbidden minor characterisation for the property of having a normal spanning tree.
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