Proof of Halin’s normal spanning tree conjecture
نویسندگان
چکیده
Halin conjectured 20 years ago that a graph has normal spanning tree if and only every minor of it countable colouring number. We prove Halin’s conjecture. This implies forbidden characterisation for the property having tree.
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ژورنال
عنوان ژورنال: Israel Journal of Mathematics
سال: 2021
ISSN: ['1565-8511', '0021-2172']
DOI: https://doi.org/10.1007/s11856-021-2249-3