A spectral condition for the existence of cycles with consecutive odd lengths in non-bipartite graphs
نویسندگان
چکیده
A graph G is called H-free, if it does not contain H as a subgraph. In 2010, Nikiforov proposed Brualdi-Solheid-Turán type problem: what the maximum spectral radius of an H-free order n? this paper, we consider problem for non-bipartite graphs. Let Ka,b•K3 denote obtained by identifying vertex Ka,b in part size b and K3. We prove that n satisfying ρ(G)≥ρ(K⌈n−22⌉,⌊n−22⌋•K3), then contains all odd cycles C2l+1 each integer l∈[2,k] unless G≅K⌈n−22⌉,⌊n−22⌋•K3, provided sufficiently large with respect to k. This resolves posed Guo, Lin Zhao (2021).
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ژورنال
عنوان ژورنال: Discrete Mathematics
سال: 2023
ISSN: ['1872-681X', '0012-365X']
DOI: https://doi.org/10.1016/j.disc.2023.113365