Title
Cubic graphs with small independence ratio
Abstract
Let i(r, g) denote the infimum of the ratio alpha(G)/vertical bar V(G)vertical bar over the r-regular graphs of girth at least g, where alpha(G) is the independence number of G, and let i(r, infinity) := lim(g ->infinity) i(r, g). Recently, several new lower bounds of i(3, infinity) were obtained. In particular, Hoppen and Wormald showed in 2015 that i(3, infinity) >= 0.4375, and Csoka improved it to i(3, infinity) >= 0.44533 in 2016. Bollobas proved the upper bound i(3, infinity) < 6/13 in 1981, and McKay improved it to i(3, infinity) < 0.45537in 1987. There were no improvements since then. In this paper, we improve the upper bound to i(3, infinity) <= 0.454.
Year
Venue
Field
2019
ELECTRONIC JOURNAL OF COMBINATORICS
Discrete mathematics,Combinatorics,Cubic graph,Mathematics
DocType
Volume
Issue
Journal
26
1
ISSN
Citations 
PageRank 
1077-8926
0
0.34
References 
Authors
0
3
Name
Order
Citations
PageRank
József Balogh186289.91
Alexandr V. Kostochka268289.87
Xujun Liu301.69