Results 21 to 30 of about 735 (221)
On hamiltonicity of 1-tough triangle-free graphs
Electronic Journal of Graph Theory and Applications, 2021 Let ω(G) denote the number of components of a graph G. A connected graph G is said to be 1-tough if ω(G − X)≤|X| for all X ⊆ V(G) with ω(G − X)>1. It is well-known that every hamiltonian graph is 1-tough, but that the reverse statement is not true in ...
Wei Zheng, Hajo Broersma, Ligong Wang
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The Ryjáček Closure and a Forbidden Subgraph
Discussiones Mathematicae Graph Theory, 2016 The Ryjáček closure is a powerful tool in the study of Hamiltonian properties of claw-free graphs. Because of its usefulness, we may hope to use it in the classes of graphs defined by another forbidden subgraph. In this note, we give a negative answer to
Saito Akira, Xiong Liming
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Colouring graphs with forbidden bipartite subgraphs
Combinatorics, Probability and Computing, 2022 AbstractA conjecture of Alon, Krivelevich and Sudakov states that, for any graph $F$ , there is a constant $c_F \gt 0$ such that if $G$ is an $F$ -free graph of maximum degree $\Delta$ , then $\chi\!(G) \leqslant c_F \Delta/ \log\!\Delta$ . Alon, Krivelevich and Sudakov verified this conjecture for a class of graphs $F$ that includes all ...
James Anderson +2 more
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The graph grabbing game on {0,1}-weighted graphs
Results in Applied Mathematics, 2019 The graph grabbing game is a two-player game on a weighted connected graph in which two players, Alice and Bob, alternatively remove non-cut vertices one by one to gain the weights on them.
Soogang Eoh, Jihoon Choi
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Hereditary Equality of Domination and Exponential Domination in Subcubic Graphs
Discussiones Mathematicae Graph Theory, 2021 Let γ(G) and γe(G) denote the domination number and exponential domination number of graph G, respectively. Henning et al., in [Hereditary equality of domination and exponential domination, Discuss. Math. Graph Theory 38 (2018) 275–285] gave a conjecture:
Chen Xue-Gang, Wang Yu-Feng, Wu Xiao-Fei
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Ramsey-type Theorems with Forbidden Subgraphs [PDF]
Combinatorica, 2001 P. Erdős and A. Hajnal conjectured that for every finite graph \(H\) every \(H\)-free graph on \(n\) vertices contains a complete or empty subgraph of size \(n^{\varepsilon(H)}\). It is shown that if the conjecture holds for \(H_1\), \(H_2\) then it holds for the graph which is \(H_1\) with one vertex blown up to a copy of \(H_2\).
Alon, Noga +2 more
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Electronic Journal of Graph Theory and Applications, 2018 We find the structure of graphs that have no C4, $\overline{C}_4$, C5, S3, chair and co-chair as induced subgraphs. Then we deduce the structure of the graphs having no induced C4, $\overline{C_4}$, S3, chair and co-chair and the structure of the graphs ...
Salman Ghazal
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Coloring graphs characterized by a forbidden subgraph [PDF]
Discrete Applied Mathematics, 2014 zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Petr A. Golovach +2 more
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Discrete Mathematics & Theoretical Computer Science, 2018 We define a weakly threshold sequence to be a degree sequence $d=(d_1,\dots,d_n)$ of a graph having the property that $\sum_{i \leq k} d_i \geq k(k-1)+\sum_{i > k} \min\{k,d_i\} - 1$ for all positive $k \leq \max\{i:d_i \geq i-1\}$.
Michael D. Barrus
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Forbidden subgraphs in connected graphs
Theoretical Computer Science, 2004 Given a set $ =\{H_1,H_2,...\}$ of connected non acyclic graphs, a $ $-free graph is one which does not contain any member of $% $ as copy. Define the excess of a graph as the difference between its number of edges and its number of vertices. Let ${\gr{W}}_{k, }$ be theexponential generating function (EGF for brief) of connected $ $-free graphs ...
Ravelomanana, Vlady, Loÿs, Thimonier
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