Title:
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The contractible subgraph of $5$-connected graphs (English) |
Author:
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Qin, Chengfu |
Author:
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Guo, Xiaofeng |
Author:
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Yang, Weihua |
Language:
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English |
Journal:
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Czechoslovak Mathematical Journal |
ISSN:
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0011-4642 (print) |
ISSN:
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1572-9141 (online) |
Volume:
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63 |
Issue:
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3 |
Year:
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2013 |
Pages:
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671-677 |
Summary lang:
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English |
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Category:
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math |
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Summary:
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An edge $e$ of a $k$-connected graph $G$ is said to be $k$-removable if $G-e$ is still $k$-connected. A subgraph $H$ of a $k$-connected graph is said to be $k$-contractible if its contraction results still in a $k$-connected graph. A $k$-connected graph with neither removable edge nor contractible subgraph is said to be minor minimally $k$-connected. In this paper, we show that there is a contractible subgraph in a $5$-connected graph which contains a vertex who is not contained in any triangles. Hence, every vertex of minor minimally $5$-connected graph is contained in some triangle. (English) |
Keyword:
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5-connected graph |
Keyword:
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contractible subgraph |
Keyword:
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minor minimally $k$-connected |
MSC:
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05C40 |
MSC:
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05C83 |
idZBL:
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Zbl 06282104 |
idMR:
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MR3125648 |
DOI:
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10.1007/s10587-013-0046-9 |
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Date available:
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2013-10-07T12:02:26Z |
Last updated:
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2020-07-03 |
Stable URL:
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http://hdl.handle.net/10338.dmlcz/143483 |
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Reference:
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Reference:
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Reference:
|
[3] Fijavž, G.: Graph Minors and Connectivity. Ph.D. Thesis.University of Ljubljana (2001). |
Reference:
|
[4] Kriesell, M.: Triangle density and contractibility.Comb. Probab. Comput. 14 (2005), 133-146. Zbl 1059.05065, MR 2128086, 10.1017/S0963548304006601 |
Reference:
|
[5] Kriesell, M.: How to contract an essentially $6$-connected graph to a $5$-connected graph.Discrete Math. 307 (2007), 494-510. Zbl 1109.05062, MR 2287490, 10.1016/j.disc.2005.09.040 |
Reference:
|
[6] Mader, W.: Generalizations of critical connectivity of graphs.Proceedings of the first Japan conference on graph theory and applications. Hakone, Japan, June 1-5, 1986. Discrete Mathematics {\it 72} J. Akiyama, Y. Egawa, H. Enomoto North-Holland Amsterdam (1988), 267-283. MR 0975546, 10.1016/0012-365X(88)90216-6 |
Reference:
|
[7] Qin, C., Yuan, X., Su, J.: Triangles in contraction critical $5$-connected graphs.Australas. J. Comb. 33 (2005), 139-146. Zbl 1077.05055, MR 2170354 |
Reference:
|
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