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Claim. L. Chahua and J. Gutiérrez, On Tuza's conjecture in dense graphs, Discrete Appl. Math. 377 (2025), 225--233 (arXiv:2405.11409, v1 of 18 May 2024), prove three results on Tuza's inequality τ(G)≤2ν(G)\tau(G)\le2\nu(G), cited by the pages of arXiv v1:

  • Theorem 5 (p. 3): "Let G=(K,S,E(G))G=(K,S,E(G)) be a split graph on nn vertices. If δ(G)≥3n5\delta(G)\ge\frac{3n}5, then Conjecture 1 holds", where a split graph is one whose vertices split into a clique KK and an independent set SS, and Conjecture 1 is Tuza's.
  • Corollary 13 (p. 7), from Theorem 12 (p. 6): "For any α>0\alpha>0, every tripartite graph GG with more than (1+3α12α)n2\left(\frac{1+3\alpha}{12\alpha}\right)n^2 edges satisfies τ(G)<αν(G)\tau(G)<\alpha\nu(G). In particular, if GG has more than 33n2112\frac{33n^2}{112} edges then τ(G)<2815ν(G)\tau(G)<\frac{28}{15}\nu(G)." The abstract states the second sentence for tripartite graphs of minimum degree more than 33n56\frac{33n}{56}, which have more than 33n2112\frac{33n^2}{112} edges.
  • Theorem 15 (p. 7): "For every complete 4-partite graph GG on at least five vertices, τ(G)≤32ν(G)\tau(G)\le\frac32\nu(G). Moreover, this bound it [sic] tight."

The three results are paged at Theorem 5, Corollary 13 and Theorem 15 of the library's source card.

Covers. Split graphs on nn vertices with minimum degree at least 3n/53n/5 (Theorem 5); complete 44-partite graphs on at least five vertices, with τ≤32ν\tau\le\frac32\nu (Theorem 15); tripartite graphs on nn vertices with more than 33112n2\frac{33}{112}n^2 edges, with τ<2815ν\tau<\frac{28}{15}\nu (Corollary 13). The statement for every graph stays open.

Depends on. Nothing in this wiki; the results are the paper's own theorems.

Acceptance. Refereed: Discrete Appl. Math. 377 (2025), 225--233, per its Crossref record. The page numbers cited are those of arXiv v1, not compared with the journal text. The site does not cite the paper.

Read depth. Claims checked: the three statements and the derivation of Corollary 13 from Theorem 12; the proofs of Theorems 5 and 15 are not checked, and that of Theorem 12 is checked for structure only.