English

Tuza's Conjecture for Graphs of Maximum Average Degree Less Than 7

Combinatorics 2015-04-14 v3

Abstract

Tuza's Conjecture states that if a graph GG does not contain more than kk edge-disjoint triangles, then some set of at most 2k2k edges meets all triangles of GG. We prove Tuza's Conjecture for all graphs GG having no subgraph with average degree at least 77. As a key tool in the proof, we introduce a notion of reducible sets for Tuza's Conjecture; these are substructures which cannot occur in a minimal counterexample to Tuza's Conjecture. We also introduce weak K\"onig--Egerv\'ary graphs, a generalization of the well-studied K\"onig--Egerv\'ary graphs.

Keywords

Cite

@article{arxiv.1308.2211,
  title  = {Tuza's Conjecture for Graphs of Maximum Average Degree Less Than 7},
  author = {Gregory J. Puleo},
  journal= {arXiv preprint arXiv:1308.2211},
  year   = {2015}
}

Comments

26 pages, 11 figures. Updated with journal reference and some revisions (corrected a few minor errors, added some more background material)