M Zhai, H Lin - Journal of Combinatorial Theory, Series B, 2022 - Elsevier
Minors play a key role in graph theory, and extremal problems on forbidding minors have attracted appreciable amount of interest in the past decades. In this paper, we focus on …
M Zhai, R Liu, J Xue - The Electronic Journal of Combinatorics, 2022 - combinatorics.org
Turán-type problem is one of central problems in extremal graph theory. Erdős et al.[J. Combin. Theory Ser. B 64 (1995) 89-100] obtained the exact Turán number of the friendship …
Y Zhang, L Wang - Discrete Mathematics, 2024 - Elsevier
The gem is the 5-vertex graph consisting of a 4-vertex path plus a vertex adjacent to each vertex of the path. A graph is said to be gem-free if it does not contain gem as a subgraph. In …
L Liu, B Ning - arXiv preprint arXiv:2305.10290, 2023 - arxiv.org
Spectral graph theory is a captivating area of graph theory that employs the eigenvalues and eigenvectors of matrices associated with graphs to study them. In this paper, we present a …
H Lin, M Zhai, Y Zhao - arXiv preprint arXiv:2108.09057, 2021 - arxiv.org
In this paper, we give spectral conditions to guarantee the existence of two edge disjoint cycles and two cycles of the same length. These two results can be seen as spectral …
Y Li, L Lu, Y Peng - Discrete Mathematics, 2023 - Elsevier
Let F k be the (friendship) graph obtained from k triangles by sharing a common vertex. The F k-free graphs of order n which attain the maximal spectral radius was firstly characterized …
B Ning, M Zhai - European Journal of Combinatorics, 2023 - Elsevier
Motivated by the counting results for color-critical subgraphs by Mubayi (2010), we study the phenomenon behind Mubayi's theorem from a spectral perspective and start up this problem …
B Li, B Ning - The Electronic Journal of Combinatorics, 2023 - combinatorics.org
In the 1970s, Erdős asked how many edges are needed in a graph on $ n $ vertices, to ensure the existence of a cycle of length exactly $ nk $. In this paper, we consider the …
Let ρ (G) be the spectral radius of a graph G with m edges. Nosal's theorem states that if ρ (G)> m then G contains a triangle. In this article, we give a generalization: any non-bipartite …