$K_4$-Minor-Free Induced Subgraphs of Sparse Connected Graphs
نویسندگان
چکیده
منابع مشابه
$K_{4}$-Minor-Free Induced Subgraphs of Sparse Connected Graphs
We prove that every connected graph G with m edges contains a set X of at most 3 16 (m+ 1) vertices such that G−X has no K4 minor, or equivalently, has treewidth at most 2. This bound is best possible and improves a recent bound of 19 100m+ 3 20 due to Edwards and Farr. Connectivity is essential: If G is not connected then only a bound of 15m can be guaranteed.
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ژورنال
عنوان ژورنال: SIAM Journal on Discrete Mathematics
سال: 2018
ISSN: 0895-4801,1095-7146
DOI: 10.1137/16m107712x