Abstract
A Π-shape tree is a tree with exactly two vertices having the maximum degree three. In this paper, we classify the Π-shape trees into two types, and complete the spectral characterization for one type. Exactly, we prove that all graphs of this type are determined by their Laplacian spectra with some exceptions. Moreover, we give some L-cospectral mates of some graphs for another type.
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This work is supported by the Young Scholars Science Foundation of Lanzhou Jiaotong University (No. 2016014) and NSFC (Nos. 11531011, 11671344, 11461038, 61163010).
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Wen, F., Huang, Q., Huang, X. et al. On the Laplacian spectral characterization of Π-shape trees. Indian J Pure Appl Math 49, 397–411 (2018). https://doi.org/10.1007/s13226-018-0276-5
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DOI: https://doi.org/10.1007/s13226-018-0276-5