Title:
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Minimum degree, leaf number and traceability (English) |
Author:
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Mukwembi, Simon |
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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2 |
Year:
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2013 |
Pages:
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539-545 |
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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Let $G$ be a finite connected graph with minimum degree $\delta $. The leaf number $L(G)$ of $G$ is defined as the maximum number of leaf vertices contained in a spanning tree of $G$. We prove that if $\delta \ge \frac {1}{2}(L(G)+1)$, then $G$ is 2-connected. Further, we deduce, for graphs of girth greater than 4, that if $\delta \ge \smash {\frac {1}{2}}(L(G)+1)$, then $G$ contains a spanning path. This provides a partial solution to a conjecture of the computer program Graffiti.pc [DeLaVi na and Waller, Spanning trees with many leaves and average distance, Electron. J. Combin. 15 (2008), 1–16]. For $G$ claw-free, we show that if $\delta \ge \frac {1}{2}(L(G)+1)$, then $G$ is Hamiltonian. This again confirms, and even improves, the conjecture of Graffiti.pc for this class of graphs. (English) |
Keyword:
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interconnection network |
Keyword:
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graph |
Keyword:
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leaf number |
Keyword:
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traceability |
Keyword:
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Hamiltonicity |
Keyword:
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Graffiti.pc |
MSC:
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05C45 |
idZBL:
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Zbl 06236430 |
idMR:
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MR3073977 |
DOI:
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10.1007/s10587-013-0036-y |
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Date available:
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2013-07-18T15:08:55Z |
Last updated:
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2020-07-03 |
Stable URL:
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http://hdl.handle.net/10338.dmlcz/143331 |
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Reference:
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Reference:
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Reference:
|
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Reference:
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Reference:
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