On the spectral radius of graphs without a star forest
نویسندگان
چکیده
Let F=∪i=1kSdi be the union of pairwise vertex-disjoint k stars order d1+1,…,dk+1, respectively, where k≥2 and d1≥⋯≥dk≥1. In this paper, we present two sharp upper bounds for spectral radius F-free (bipartite) graphs characterize all corresponding extremal graphs. Moreover, minimum least eigenvalue adjacency matrix an graph are obtained.
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ژورنال
عنوان ژورنال: Discrete Mathematics
سال: 2021
ISSN: ['1872-681X', '0012-365X']
DOI: https://doi.org/10.1016/j.disc.2020.112269