Title
Decomposition of Sparse Graphs into Forests and a Graph with Bounded Degree.
Abstract
For a loopless multigraph G, the fractional arboricity Arb(G) is the maximum of <mml:mfrac>|E(H)||V(H)|-1 over all subgraphs H with at least two vertices. Generalizing the Nash-Williams Arboricity Theorem, the Nine Dragon Tree Conjecture asserts that if Arb (G)k+d/k+d+1, then G decomposes into k+1 forests with one having maximum degree at most d. The conjecture was previously proved for (k,d){(1,1),(1,2)}; we prove it for d=k+1 and when k=1 and d6. For (k,d)=(1,2), we can further restrict one forest to have at most two edges in each component. For general (k,d), we prove weaker conclusions. If d>k, then Arb (G)k+d/k+d+1</mml:mfrac> implies that G decomposes into k forests plus a multigraph (not necessarily a forest) with maximum degree at most d. If dk, then Arb (G)k+d/2k+2</mml:mfrac> implies that G decomposes into k+1 forests, one having maximum degree at most d. Our results generalize earlier results about decomposition of sparse planar graphs. (C) 2013 Wiley Periodicals, Inc. J. Graph Theory 74: 369-391, 2013
Year
DOI
Venue
2013
10.1002/jgt.21711
JOURNAL OF GRAPH THEORY
Keywords
Field
DocType
graph decomposition,forest,fractional arboricity,maximum average degree,discharging
Discrete mathematics,Topology,Combinatorics,Multigraph,Vertex (geometry),Generalization,Degree (graph theory),Conjecture,Arboricity,Mathematics,Planar graph,Bounded function
Journal
Volume
Issue
ISSN
74.0
4.0
0364-9024
Citations 
PageRank 
References 
9
0.73
9
Authors
5
Name
Order
Citations
PageRank
Seog-Jin Kim115117.63
Alexandr V. Kostochka268289.87
Douglas B. West31176185.69
Hehui Wu4647.40
Xuding Zhu51883190.19