Title
Turan Numbers For Disjoint Paths
Abstract
The Turan number of a graph H, ex ( n , H ), is the maximum number of edges in a graph of order n that does not contain a copy of H as a subgraph. LidickATIN SMALL LETTER Y WITH ACUTE, Liu and Palmer determined ex ( n , F k 1 , horizontal ellipsis , k m ) for sufficiently large n and proved that the extremal graph is unique, where F k 1 , horizontal ellipsis , k m is the union of pairwise vertex-disjoint paths on k 1 , horizontal ellipsis , k m vertices. There are a few kinds of graphs F for which ex ( n , F ) are known exactly for all n, including cliques, matchings, paths, cycles on odd number of vertices and some other special graphs. In this paper, using a different approach from LidickATIN SMALL LETTER Y WITH ACUTE, Liu and Palmer, we determine ex ( n , F k 1 , horizontal ellipsis , k m ) for all integers n when at most one of k 1 , horizontal ellipsis , k m is odd. Furthermore, we show that there exists a family of pairs of bipartite graphs ( F , G ) such that ex ( n , F ) = ex ( n , G ) for all integers n, which is related to an old problem of Erdos and Simonovits.
Year
DOI
Venue
2021
10.1002/jgt.22710
JOURNAL OF GRAPH THEORY
Keywords
DocType
Volume
disjoint path, extremal graph, Turan number
Journal
98
Issue
ISSN
Citations 
3
0364-9024
2
PageRank 
References 
Authors
0.44
0
2
Name
Order
Citations
PageRank
Long-Tu Yuan120.44
Xiao-Dong Zhang29719.87