## Abstract Vizing's conjecture from 1968 asserts that the domination number of the Cartesian product of two graphs is at least as large as the product of their domination numbers. In this paper we survey the approaches to this central conjecture from domination theory and give some new results alo
A partition approach to Vizing's conjecture
✍ Scribed by Chen, Guantao; Piotrowski, Wiktor; Shreve, Warren
- Publisher
- John Wiley and Sons
- Year
- 1996
- Tongue
- English
- Weight
- 411 KB
- Volume
- 21
- Category
- Article
- ISSN
- 0364-9024
No coin nor oath required. For personal study only.
✦ Synopsis
In 1963, Vizing [Vichysl. Sistemy 9 (19631, 30-431
conjectured that y ( G X H) 2 y ( G ) y ( H ) , where G X Hdenotes the Cartesian product of graphs, and y(G) is the domination number. In this paper we define the extraction number x(G) and w e prove that
M G ) 5 x(G) 5 y(G), and y ( G x H) 2 x(G)y(H),
where Pz(G) is the 2-packing number of G. Though the equality x(G) = y(G) is proven to hold in several classes of graphs, w e construct an infinite family of graphs which do not satisfy this condition. Also, we show the following lower bound: y ( G X H) 2 y(G)Pz(H) + Pz(G) ( y ( H ) -P,(H)).
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