Abstract
Let G be an undirected and loopless finite graph that is not a path. The smallest integer m such that the iterated line graph Lm(G) is hamiltonian is called the hamiltonian index of G, denoted by h(G). A reduction method to determine the hamiltonian index of a graph G with h(G)≥2 is given here. We use it to establish a sharp lower bound and a sharp upper bound on h(G), respectively, thereby improving some known results of Catlin et al. [J. Graph Theory 14 (1990) 347] and Hong-Jian Lai [Discrete Math. 69 (1988) 43]. Examples show that h(G) may reach all integers between the lower bound and the upper bound. We also propose some questions on the topic.
Original language | English |
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Pages (from-to) | 279-288 |
Number of pages | 10 |
Journal | Discrete Mathematics |
Volume | 285 |
Issue number | 1-3 |
DOIs | |
Publication status | Published - 6 Aug 2004 |
Keywords
- Branch-bond
- Hamiltonian index
- Iterated line graph
- Reduction method