We give a simple proof that the obvious necessary conditions for a graph to contain the k th power of a Hamiltonian path are sufficient for the class of interval graphs. The proof is based on showing that a greedy algorithm tests for the existence of Hamiltonian path powers in interval graphs. We wi
Pebbling in diameter two graphs and products of paths
β Scribed by Clarke, T. A.; Hochberg, R. A.; Hurlbert, G. H.
- Publisher
- John Wiley and Sons
- Year
- 1997
- Tongue
- English
- Weight
- 151 KB
- Volume
- 25
- Category
- Article
- ISSN
- 0364-9024
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β¦ Synopsis
Results regarding the pebbling number of various graphs are presented. We say a graph is of Class 0 if its pebbling number equals the number of its vertices. For diameter d we conjecture that every graph of sufficient connectivity is of Class 0. We verify the conjecture for d = 2 by characterizing those diameter two graphs of Class 0, extending results of Pachter, Snevily and Voxman. In fact we use this characterization to show that almost all graphs have Class 0. We also present a technical correction to Chung's alternate proof of a number theoretic result of Lemke and Kleitman via pebbling.
π SIMILAR VOLUMES
It is known that for each d there exists a graph of diameter two and maximum degree d which has at least (d/2) (d + 2)/2 vertices. In contrast with this, we prove that for every surface S there is a constant d S such that each graph of diameter two and maximum degree d β₯ d S , which is embeddable in
## Abstract A twoβphase flashing flow model is developed to predict the distributions of pressure, temperature, velocity and evaporation rate in a transfer line, which is a typical example of a twoβphase flow pipe in the petrochemical industry. The model is proposed based on the pressure drop model