| Title:
             | 
The upper traceable number of a graph (English) | 
| Author:
             | 
Okamoto, Futaba | 
| Author:
             | 
Zhang, Ping | 
| Author:
             | 
Saenpholphat, Varaporn | 
| Language:
             | 
English | 
| Journal:
             | 
Czechoslovak Mathematical Journal | 
| ISSN:
             | 
0011-4642 (print) | 
| ISSN:
             | 
1572-9141 (online) | 
| Volume:
             | 
58 | 
| Issue:
             | 
1 | 
| Year:
             | 
2008 | 
| Pages:
             | 
271-287 | 
| Summary lang:
             | 
English | 
| . | 
| Category:
             | 
math | 
| . | 
| Summary:
             | 
For a nontrivial connected graph $G$ of order $n$ and a linear ordering $s\: v_1, v_2, \ldots , v_n$ of vertices of $G$, define $d(s) = \sum _{i=1}^{n-1} d(v_i, v_{i+1})$. The traceable number $t(G)$ of a graph $G$ is $t(G) = \min \lbrace d(s)\rbrace $ and the upper traceable number $t^+(G)$ of $G$ is $t^+(G) = \max \lbrace d(s)\rbrace ,$ where the minimum and maximum are taken over all linear orderings $s$ of vertices of $G$. We study upper traceable numbers of several classes of graphs and the relationship between the traceable number and upper traceable number of a graph. All connected graphs $G$ for which $t^+(G)- t(G) = 1$ are characterized and a formula for the upper traceable number of a tree is established. (English) | 
| Keyword:
             | 
traceable number | 
| Keyword:
             | 
upper traceable number | 
| Keyword:
             | 
Hamiltonian number | 
| MSC:
             | 
05C12 | 
| MSC:
             | 
05C45 | 
| idZBL:
             | 
Zbl 1174.05040 | 
| idMR:
             | 
MR2402537 | 
| . | 
| Date available:
             | 
2009-09-24T11:54:48Z | 
| Last updated:
             | 
2020-07-03 | 
| Stable URL:
             | 
http://hdl.handle.net/10338.dmlcz/128257 | 
| . | 
| Reference:
             | 
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| . |