A unified existence theorem for normal spanning trees
نویسندگان
چکیده
منابع مشابه
A Simple Existence Criterion for Normal Spanning Trees
Halin proved in 1978 that there exists a normal spanning tree in every connected graph G that satisfies the following two conditions: (i) G contains no subdivision of a ‘fat’ Kא0 , one in which every edge has been replaced by uncountably many parallel edges; and (ii) G has no Kא0 subgraph. We show that the second condition is unnecessary.
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ژورنال
عنوان ژورنال: Journal of Combinatorial Theory, Series B
سال: 2020
ISSN: 0095-8956
DOI: 10.1016/j.jctb.2020.07.002