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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